Dark Chocolate Mousse Cake

This super moist dark chocolate mousse cake combines unsweetened natural cocoa powder and dark cocoa powder for an extra rich flavor. Fill the cake with a simplified chocolate mousse and cover the whole dessert with semi-sweet chocolate ganache. If needed, you can prepare the ganache and mousse ahead of time.

slice of dark chocolate mousse cake on a cake server

Chocolate mousse is simple divinity in its own right, but when paired with chocolate cake, it’s downright decadent. And then add chocolate ganache to the mix? Have mercy.

This spectacularly rich chocolate cake is such a personal and reader favorite that I knew I had to include it in my cookbook, Sally’s Baking 101 (which has become a New York Times Best Seller!). The cakes chapter just would not have been complete without it!

It’s actually the first recipe in that chapter, and in the book it’s titled “Chocolate Ganache Cake: 2 Ways,” because I include a second filling option—peanut butter frosting instead of chocolate mousse, just like this recipe for dark chocolate peanut butter cake. Both versions of ganache-topped chocolate layer cakes have received such glowing reviews on my website, I simply couldn’t choose between them… so I found a way to include them both!


This cake basically demands a huge gathering because—trust me—you don’t want to be left alone with its temptation. It WILL call out your name each time you open the refrigerator.

Taunting you.

One reader, Judy, commented:Don’t make this cake unless you want everyone who has a bite to request that you make it for every special occasion for the rest of time 🙂 I do four layers and follow the recipe exactly, and it has come out perfectly every time. I’ve already made at least ten of these cakes. Fabulous! ★★★★★

One reader, Cecilia, commented:OMG! This cake is absolutely divine! It’s a chocolate lover’s dream. The chocolate mousse is heavenly. I made it for my niece’s birthday and ended up making a four-layer cake. There were no leftovers. I don’t need any other chocolate cake recipe. This is it! Definitely the best! ★★★★★

One reader, Brittney, commented:This cake turned out amazing! I made it for a birthday party… and it was requested to be the new ‘party cake’! ★★★★★

chocolate layer cake on a wooden cake stand

3 Parts to Dark Chocolate Mousse Cake

Let’s break down each component of this intensely rich cake:

  1. Dark Chocolate Cake: This is actually a variation of my tuxedo cake, which originated from my chocolate cake recipe. In recent years, I’ve found that replacing sour cream for some of the buttermilk gives the cake more structure.
  2. Chocolate Mousse: I researched simplified ways to make a fluffy chocolate mousse filling without the use of eggs or gelatin. This chocolate mousse filling combines real chocolate and homemade whipped cream. Or our whipped frosting would make a wonderful alternative filling if you don’t want to make the chocolate mousse!
  3. Chocolate Ganache: Top the whole cake with 2 ingredient semi-sweet chocolate ganache. You should be a chocolate ganache pro by now!

Video Tutorial: Chocolate Mousse Cake

Stick-to-the-back-of-your-fork moist. This is every chocolate lover’s dream!

4 layer chocolate cake

Dark Chocolate Cake

Use this chocolate cake as the starting point. For a sturdier, yet moister crumb, swap some sour cream in for the buttermilk and reduce the hot liquid. The acidity in both sour cream and buttermilk is a must to properly leaven this cake. (If desired, see my posts on Baking Powder vs Baking Soda and Baking with Buttermilk for more information.) This cake has a natural dark chocolate taste, but to deepen that flavor, use a mix of natural cocoa and Hershey’s Special Dark cocoa powder. A touch of espresso powder and hot coffee further enhances the chocolate flavor. The cake will not taste like coffee. Rather, the two add depth to the cake’s chocolate flavor.

  • Why hot liquid? The hot liquid encourages the cocoa powder to bloom and dissolve. If you don’t drink coffee, you can use hot water.

You have options! You can make this cake into 2, 3, or 4 layers. I highly recommend 3 or 4 layers because there’s over 4 cups of chocolate mousse to spread inside. You can use 8 inch or 9 inch pans. The bake times are similar, see recipe notes.

A cup of chocolate chips adds even more chocolate flavor. I used 1 cup (180g) of mini semi-sweet chocolate chips in this pictured cake, but left them out in the video. They’re optional, but definitely worth the addition!!

You can also see this exact cake batter baked as three layers in both my chocolate peanut butter cake and chocolate raspberry cake (try one of those next!).

chocolate cake batter in glass bowl

Simplified Chocolate Mousse

The chocolate mousse adds a creamy and light contrast to the dark chocolate layers. You need 6 ingredients:

  1. Hot Water
  2. Cocoa Powdernatural or dutch-process
  3. Melted Chocolateuse two 4-ounce chocolate baking bars found in the baking aisle
  4. Heavy Cream
  5. Confectioners’ Sugar
  6. Vanilla Extract

Whisk the hot water and cocoa powder together. Pour into melted chocolate. The hot water breaks up the chocolate, adding to the airy mousse consistency. Cocoa powder creates additional chocolate flavor. Fold this chocolate mixture into whipped cream—a combination of heavy cream, confectioners’ sugar, and vanilla extract.

2 images of making chocolate mousse including whipped cream and chocolate mixture in glass bowls

Whipped cream + our chocolate mixture. ↑

Fold them together to make our chocolate mousse filling. ↓

chocolate mousse for chocolate cake in glass bowl and between cake layers

Baker’s Tip: The chocolate mousse must chill in the refrigerator before using, so it’s a good idea to make it ahead of time or as the chocolate cake layers are cooling. The mousse is best cold, so I actually recommend serving the cake cold. (Additionally, the cake is much easier to assemble if the mousse is cold!)

By the way, this chocolate mousse also makes for a wonderful alternate filling in homemade eclairs!

2 images of chocolate ganache in glass bowl and pouring on chocolate cake

Chocolate Ganache

I won’t go into a lot of detail about the chocolate ganache because I have a complete chocolate ganache tutorial for you! Like the chocolate mousse, it’s imperative to use pure chocolate. Wait about 20 minutes for the ganache to thicken before pouring onto the cake.

How to Assemble & Decorate Chocolate Mousse Cake

Chocolate ganache enrobes 4 cake layers and 3 mousse layers. Place bottom cake layer on your cake stand or serving plate. Using a large icing spatula, evenly cover the top with about 1.5 cups of chilled chocolate mousse. Top with 2nd cake layer and another 1.5 cups of mousse. Top with the third cake layer, then spread another 1.5 cups mousse evenly on top. (Save a large spoonful of mousse for a thin crumb coat.) Top with final 4th cake layer. Spread any remaining mousse around the sides as a crumb coat. Run a bench scraper around the cake to smooth it out. Refrigerate cake for at least 1 hour and up to 4 hours. Chocolate mousse is pretty fluffy, so the cake won’t hold its shape unless it’s properly chilled.

Pour ganache on top then run a bench scraper around the sides to smooth it out. You can serve the cake immediately or wait for the chocolate ganache to set. 🙂

top of chocolate mousse cake with berries and chocolate shavings
slice of chocolate mousse cake on a white plate

What About Cupcakes?

Instead of a big cake, you can make chocolate mousse cupcakes. Use my chocolate cupcakes recipe and halve the chocolate mousse and chocolate ganache recipes below. Fill the cupcakes with chocolate mousse using my Sugar Plum Fairy Cupcakes as an example. Drizzle cooled cupcakes with ganache. Eat your heart out!

You can also use the chocolate mousse instead of pastry cream in homemade mille-feuille!

More Indulgent Chocolate Desserts

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4 layer chocolate cake

Dark Chocolate Mousse Cake

5 Stars 4 Stars 3 Stars 2 Stars 1 Star 4.9 from 403 reviews
  • Author: Sally McKenney
  • Prep Time: 2 hours, 30 minutes (includes chilling)
  • Cook Time: 25 minutes
  • Total Time: 5 hours, 55 minutes (includes cooling)
  • Yield: serves 12
  • Category: Cake
  • Method: Baking
  • Cuisine: American
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Description

This super moist dark chocolate cake combines unsweetened natural cocoa powder and dark cocoa powder for an extra rich flavor. Fill the cake with a simplified chocolate mousse and cover it with semi-sweet chocolate ganache. If needed, you can prepare the ganache and mousse ahead of time (see Notes). This recipe is also in my New York Times best-selling cookbook, Sally’s Baking 101.


Ingredients

  • 1 and 3/4 cups (219g) all-purpose flour (spooned & leveled)
  • 1 and 3/4 cups (350g) granulated sugar
  • 3/4 cup (64g) unsweetened natural cocoa powder* (see Notes)
  • 2 teaspoons espresso powder (optional)*
  • 2 teaspoons baking soda
  • 1 teaspoon baking powder
  • 1 teaspoon salt
  • 3/4 cup (180g) full-fat sour cream, at room temperature
  • 1/2 cup (113g/120ml) vegetable oil
  • 2 large eggs, at room temperature
  • 1/2 cup (120g/ml) buttermilk, at room temperature*
  • 2 teaspoons pure vanilla extract
  • 1/2 cup (120g/ml) hot water or black coffee*
  • 1 cup (170g) semi-sweet mini chocolate chips tossed in 1 Tbsp flour (optional)

Chocolate Mousse

  • 1/2 cup (120g/ml) hot water
  • 1/4 cup (21g) unsweetened natural or Dutch-process cocoa powder
  • 8 ounces (226g) quality semi-sweet chocolate, finely chopped*
  • 2 cups (480g/ml) heavy cream, cold
  • 2 Tablespoons confectioners’ sugar
  • 1/2 teaspoon pure vanilla extract

Chocolate Ganache

  • 8 ounces (226g) quality semi-sweet chocolate, finely chopped
  • 1 cup (240g/ml) heavy cream
  • optional, for garnish: fresh berries and/or chocolate shavings


Instructions

  1. Preheat the oven to 350°F (177°C). Grease four 8-inch or 9-inch cake pans, line with parchment paper rounds, then grease the parchment paper. Parchment paper helps the cakes seamlessly release from the pans. (If it’s helpful, see this parchment paper rounds for cakes video & post.)
  2. Make the cake: In a large bowl, whisk the flour, sugar, cocoa powder, espresso powder, baking soda, baking powder, and salt together. Set aside.
  3. In another large bowl using a handheld or stand mixer fitted with a whisk attachment (or you can use a whisk) mix the sour cream, oil, and eggs together on medium-high speed until combined. Add the buttermilk and vanilla and mix until combined. Pour the dry ingredients into the wet ingredients, add the hot water/coffee, and whisk or beat on low speed until combined. Fold in the floured mini chocolate chips, if using. Divide the batter evenly among the prepared pans.
  4. Bake for 19–23 minutes. Baking times vary, so keep an eye on yours. The cakes are done when a toothpick inserted in the center comes out clean. Cool the cakes in the pans set on a cooling rack for 1 hour. Run a knife around the edges to help loosen the sides, remove the cakes from the pans, peel off the parchment, and place on the rack to finish cooling. The cakes may slightly sink in the middle as they cool—that’s expected.
  5. Make the chocolate mousse: In a small bowl, whisk the hot water and cocoa powder together until smooth. Melt the chopped chocolate in a double boiler or use the microwave. If using the microwave: place the chopped chocolate in a medium heat-proof bowl. Microwave for 20-second increments, stirring after each increment until completely melted and smooth. Pour hot water/cocoa mixture into the melted chocolate and stir until thick and smooth. Set aside. In a large bowl using a handheld or stand mixer fitted with a whisk attachment, whip the heavy cream, confectioners’ sugar, and vanilla extract together on medium-high speed until medium peaks form, about 3 minutes. Medium peaks are between soft/loose peaks and stiff peaks. Pour in the chocolate mixture and gently fold together with a spatula. Do not overmix, as this could deflate it. Cover the mousse and refrigerate for at least 2 hours or up to 2 days. Makes about 4.5 cups (about 900g).
  6. Assemble the cake before preparing chocolate ganache: First, level the cakes (if needed): using a large serrated knife, slice a thin layer off the tops of the cakes to create a flat surface. Place 1 cake layer on your cake stand, cake turntable, or serving plate. Using a large icing spatula, evenly cover the top with about 1.5 cups (200g) of chocolate mousse. Top with the second layer, upside down, and evenly cover the top with the same amount of chocolate mousse. Top with the third cake layer, right side up, and again cover with the same amount of mousse. Top with final cake layer. Spread the remaining mousse on top and around the sides of the cake as a crumb coat. Run a bench scraper around the cake to smooth out the sides. Refrigerate for at least 1 hour and up to 4 hours. Prepare the ganache while the cake is chilling. 
  7. Make the chocolate ganache: Place the chocolate in a medium heat-proof bowl. In a small saucepan, heat the cream over medium heat just until it begins to gently simmer. (Do not let it come to a rapid boil—that’s too hot!) Pour the warm cream over the chocolate and let it sit for 2–3 minutes to gently soften the chocolate. With a metal spoon or small spatula, slowly stir until the chocolate has melted and the mixture is smooth. The finer you chopped the chocolate, the quicker it will melt with the cream. If it’s not melting, do not microwave it. If needed, see Troubleshooting Chocolate Ganache. Refrigerate the ganache for at least 30 minutes or up to 1 hour to thicken.
  8. Pour/spoon the thickened ganache on the chilled cake. Smooth the top and sides with an icing spatula. Top with optional garnish such as fresh berries and/or chocolate shavings. Serve cake immediately or chill, uncovered, for up to 4–6 hours before serving. Cake can be served at room temperature or chilled.
  9. Cover leftover cake tightly and store in the refrigerator for up to 5 days.

Notes

  1. Make Ahead & Freezing Instructions: Prepare cake through step 4. Wrap the individual baked and cooled cake layers tightly and refrigerate for up to 2 days or freeze up to 3 months. Bring to room temperature, make mousse filling, then continue with step 6. You can prepare the chocolate mousse in advance. See step 5. You can also prepare the chocolate ganache ahead of time too. Refrigerate prepared ganache for up to 3 days. Bring to room temperature before spreading onto cake. You can freeze cake for up to 3 months. Thaw overnight in the refrigerator, then bring to room temperature or serve cold. See How to Freeze Cakes for more information.
  2. Special Tools (affiliate links): 8-inch Round Cake Pans or 9-inch Round Cake Pans | Glass Mixing Bowl | Whisk | Electric Mixer (Handheld or Stand) | Cooling Rack | Double Boiler | Cake Stand or Cake Turntable | Large Icing Spatula | Bench Scraper | Cake Carrier (for storage)
  3. 3-Layer Cake: You can also prepare this as a 3-layer cake. Divide batter between three 8-inch or 9-inch cake pans in step 1 and bake for 24–26 minutes or until a toothpick inserted in the center comes out clean. Use about 2 cups of chocolate mousse between each layer.
  4. Espresso Powder/Coffee: Espresso powder and coffee will not make the cake taste like coffee. Rather, they deepen the chocolate flavor. I highly recommend them both. You can find espresso powder in the baking aisle at many grocery stores or online. If coffee isn’t your thing, you can leave out the espresso powder and use hot water instead of the hot coffee.
  5. Cocoa Powder: For the best dark chocolate flavor in the cake, I recommend using a blend of unsweetened natural cocoa powder (1/4 cup; 21g) and Hershey’s “Special Dark” cocoa powder (1/2 cup; 43g). Hershey’s Special Dark is actually a mix of natural cocoa powder (an acid) and Dutch-process cocoa powder (a base) and it worked fine in this recipe. This recipe needs acidic natural cocoa powder, so do not use ALL Dutch-process cocoa powder. For best results, use 3/4 cup (64g) natural or the blend of natural/Special Dark I used. For the chocolate mousse, you can use either unsweetened natural or Dutch-process cocoa powder (or the Hershey’s Special Dark).
  6. Why Room Temperature? All refrigerated items should be at room temperature so the batter mixes together easily and evenly. Read more about why room-temperature ingredients are important. Instead of sour cream, you can use plain yogurt. The cake won’t taste as rich, but it’s a fine substitute.
  7. Buttermilk: Buttermilk is required for this recipe. You can make your own DIY buttermilk substitute if needed. Add 1 teaspoon of white vinegar or lemon juice to a liquid measuring cup. Then add enough whole milk to the same measuring cup until it reaches 1/2 cup. (In a pinch, lower-fat or nondairy milks work for this soured milk, but the cake won’t taste as moist or rich.) Stir it around and let sit for 5 minutes. The homemade “buttermilk” will be somewhat curdled and ready to use in the recipe.
  8. Chocolate in Mousse & Ganache: Mousse & ganache will only set if the correct chocolate is used. You can use high-quality chocolate chips if needed (I prefer Ghirardelli semi-sweet chocolate chips), but I recommend using pure chocolate baking bars. You can find them right next to the chocolate chips in the baking aisle. They are sold in 4-ounce (113g) bars. I like Baker’s or Ghirardelli brands.
sally mckenney headshot purple shirt.
About the Author

Sally McKenney

Sally McKenney is a baker, food photographer, and New York Times best-selling author. Her kitchen-tested recipes and step-by-step tutorials have given millions of readers the knowledge and confidence to bake from scratch. Sally’s work has been featured on TODAY, Good Morning America, Taste of Home, People, and more.

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Reader Comments and Reviews

  1. Greg Winterhalter says:
    June 7, 2025

    Great recipe.
    Any suggestions to make cake more moist and fluffy. Mine seemed a little dense. Also my ganache seemed too fluid and wouldn’t harden on cake. Thanks

    Reply
    1. Michelle @ Sally's Baking says:
      June 7, 2025

      Hi Greg, Usually a dense, rubbery cake has been over-mixed. Be very careful to just mix the batter until combined. Here’s more tips for preventing dense cake!

      Reply
  2. Francine says:
    June 6, 2025

    This recipe says it’s for Four 8 or 9 inch pans, but it only filled the tin up about a quarter of the way. That seems like a very thin layer! I guess I’ll see how it turns out!

    Reply
  3. Rosa Ricks says:
    June 5, 2025

    Hi Sally. I live in Australia and can’t find the Hershey’s special dark cocoa powder and it’s out of stock on Amazon. Given that it is a blend of unsweetened cocoa and Dutch process powder what wis the ratio if I was to make my own. I do have the Hersheys unsweetened and I can source the Dutch process powder but I would need to know the ratio. I hope you can answer soon as I want to make this for my grandson’s birthday this weekend. Thanks Rosa

    Reply
    1. Beth @ Sally's Baking says:
      June 5, 2025

      Hi Rosa, we recommend using natural cocoa powder in the cake batter, and Dutch-process cocoa in the frosting. No need to try to recreate the Hershey’s Special Dark cocoa blend. Enjoy the cake!

      Reply
    2. Cyndi says:
      June 11, 2025

      I want to give this a go for my husband’s birthday. Just wondering if I could swap melted cooled butter for the oil or use avacado/grape seed oil insteadof veg oil?

      Reply
      1. Lexi @ Sally's Baking says:
        June 12, 2025

        Hi Cyndi, we don’t recommend butter as it will dry out the cake a bit, but you could try avocado or grape seed oil instead. Hope the cake is a hit!

  4. Meaghan Rose says:
    June 4, 2025

    I make a lot of cakes and this is one of my faves of all time. I did 3 x 6” pans and cut the layers in half to make a 6 layer cake. I alternated mousse and chocolate buttercream in between the layers. Put a crumb coat of chocolate buttercream on outside with ganache drip and chocolate shavings on top. The cake itself is so moist and flavorful… I’m still dreaming of it! Thank you Sally!

    Reply
  5. Julia says:
    June 2, 2025

    Hi! I was wondering if you happened to have an estimate for the amount of volume in total the cake batter comes out to be? I’ll have to bake in batches since I only have 2 cake pans, but want to make sure the layer thicknesses are as close as possible. Thank you!

    Reply
    1. Lexi @ Sally's Baking says:
      June 2, 2025

      Hi Julia, This recipe yields about 6 cups of batter. We hope you enjoy the cake!

      Reply
  6. Kareb says:
    May 29, 2025

    Do you think this mousse filling would work for a sheet cake? I’m thinking about doubling the cake recipe and cooking it in two half sheet pans, and then using the mousse as the filling in the middle, but I don’t know if it’s got enough structural integrity since the cake is so big?

    Reply
    1. Lexi @ Sally's Baking says:
      May 30, 2025

      Hi Kareb, that shouldn’t be a problem! Let us know how it goes for you.

      Reply
  7. 2SwanBaker says:
    May 29, 2025

    Wow, what a cake! Everybody loved it!
    And 2nd time around, I got a handshake 🙂
    But also a request/comment (yes, from my 17yo handshake giver)
    Possibility of adding a fruit compote (strawberry, raspberry, etc.) for one or two of the mousse layers

    Reply
  8. Catherine Rye says:
    May 28, 2025

    can i make this with just 2 layers? would i just divide the recipe in half including the mousse?

    Reply
    1. Trina @ Sally's Baking says:
      May 28, 2025

      Hi Catherine, yes, you can halve the recipe for a smaller cake.

      Reply
  9. kyrsten Boudreaux says:
    May 9, 2025

    If I were to make the chocolate cupcakes and fill with the mousse. Can I use the mousse as the icing as well?

    Reply
    1. Lexi @ Sally's Baking says:
      May 9, 2025

      Hi Krysten, you can certainly do that. Enjoy!

      Reply
  10. Seren Waldman says:
    May 7, 2025

    Hi Sally,
    I’ve made this before as written and it’s amazing! Is there a way to make the cake gluten free?
    Thanks!

    Reply
    1. Beth @ Sally's Baking says:
      May 8, 2025

      Hi Seren, we haven’t tried making this cake with gluten-free flour, so are unsure of the results. If you try it with a 1:1/cup-for-cup gf flour, please let us know how it goes!

      Reply
  11. Les says:
    May 7, 2025

    Great recipe! Thanks. Is it possible to freeze the mousse? Thanks in advance 🙂

    Reply
    1. Lexi @ Sally's Baking says:
      May 7, 2025

      Hi Les, You can freeze mousse, but the texture is always a little different after thawing. It’s not quite as light and airy. If you’re looking to make the cake ahead, we’d recommend freezing the individual cake layers and then making the mousse fresh when you’re ready to assemble.

      Reply
  12. Jade says:
    May 6, 2025

    Hi! If i only have two 8×3 Round pans, would this batter be okay if I left it out on the counter while I bake the other layers first?

    Reply
    1. Trina @ Sally's Baking says:
      May 6, 2025

      Hi Jade, certainly! You can bake two layers and keep the unused batter covered at room temperature until your cake pans are ready to be used again. Hope it’s a hit!

      Reply
  13. Beryl says:
    May 5, 2025

    I used a different cake recipe but made the mousse and ganache for the first time and it came out so good. Now I have some leftover mousse, so I was wondering can I freeze the mousse?

    Reply
    1. Trina @ Sally's Baking says:
      May 5, 2025

      Hi Beryl, You can freeze mousse, but the texture is always a little different after thawing. It’s not quite as light and airy. We’d recommend freezing the individual cake layers and then making the mousse fresh when you’re ready to assemble.

      Reply
  14. Amber says:
    April 25, 2025

    What is the best way to grease pan if I don’t have parchment paper?

    Reply
    1. Trina @ Sally's Baking says:
      April 25, 2025

      Hi Amber! We would grease generously with non stick spray.

      Reply
  15. Shannon Dailey says:
    April 19, 2025

    Do you think this cake would work well with buttercream icing?

    Reply
    1. Michelle @ Sally's Baking says:
      April 20, 2025

      Sure! Let us know how you like it!

      Reply
      1. Shannon says:
        April 25, 2025

        It was delicious with Sally’s chocolate buttercream!

  16. 2Swans says:
    April 17, 2025

    If I need the cake for next day.
    Should I make the Chocolate Mousse and refrigerate it;
    Make the cake and refrigerate it;
    Bring it to room temperature the next day, construct it, and only make the Ganache the next day.
    Or is it OK to assemble it all and refrigerate it for 24 Hr before serving?

    Reply
    1. Trina @ Sally's Baking says:
      April 17, 2025

      See Notes after the recipe for our recommended make-ahead instructions!

      Reply
  17. rey says:
    April 17, 2025

    Video shows you using dark cocoa but not in recipe. How much do you use or will recipe be ok with only 1 3/4 cups of regular cocoa powder.

    Reply
    1. Trina @ Sally's Baking says:
      April 17, 2025

      Hi Rey! See recipe Notes for our cocoa powder suggestions. All regular (natural) cocoa powder will work just fine here.

      Reply
    2. Lindsey says:
      May 20, 2025

      I’m not a huge chocolate cake person, but I am OBSESSED with this cake! If I wanted to make a smaller version with 6 inch cake pans, do you think halving the recipe would work?

      Reply
      1. Lexi @ Sally's Baking says:
        May 21, 2025

        Hi Lindsey, You could make this as a 6-inch cake. We’d recommend using this chocolate cupcakes recipe as the batter to make a 3 layer 6 inch cake. See our 6 inch cake recipes post as a guide. Halve the chocolate mousse and ganache from this recipe so there’s just enough. Hope this helps!

  18. DC says:
    April 9, 2025

    Hi! I wanted to make this recipe for my family but could it be made into a rectangular shape using 8in cake tins?
    Thank you!

    Reply
    1. Trina @ Sally's Baking says:
      April 9, 2025

      Hi DC! You should be able to use 8×8 pans here instead of 9 inch rounds.

      Reply
  19. Beth C says:
    April 4, 2025

    Could you add more coffee/espresso powder to make it a mocha cake? I WANT my cake to taste like coffee! 🙂

    Also wondering if you could half the recipe – what size pan(s) would you recommend?

    Reply
    1. Michelle @ Sally's Baking says:
      April 5, 2025

      Hi Beth, yes, you can halve the recipe for a smaller cake. We haven’t tested a mocha mousse recipe. You start with adding extra espresso powder – let us know if you give it a try!

      Reply
  20. Christine says:
    March 28, 2025

    When making the mousse, how do you keep the melted chocolate from seizing up after mixing in the hot water and coca powder? My mousse ended up chunky because the melted chocolate plus hot water and cocoa powder seized and got very thick.

    Reply
    1. Trina @ Sally's Baking says:
      March 28, 2025

      Hi Christine, Was the hot water/cocoa mixture still warm and the melted chocolate still fluid? The two should combine easily– you can see it in the video above. We wonder if it was the chocolate you used. We typically use Ghirardelli semi-sweet or Bakers semi-sweet baking chocolate bars.

      Reply
  21. Mary says:
    March 27, 2025

    Hi Sally! Would this cake be sturdy enough to make a sphere cake using 2 8inch hemisphere pans? Also, would milk chocolate work for the mousse, or do you think it would be too sweet?

    Reply
    1. Trina @ Sally's Baking says:
      March 27, 2025

      Hi Mary, we’re unsure about using hemisphere pans, we’re afraid it may be too much batter to bake though well. But let us know if you try. You could use milk chocolate – just be sure that they are still pure baking chocolate bars.

      Reply
  22. Beckie says:
    March 26, 2025

    Any suggestions for making these into cakes with the mouse as a filling?

    Reply
    1. Lexi @ Sally's Baking says:
      March 26, 2025

      Hi Beckie, Sure can. See “What About Cupcakes?” section in the post for more details.

      Reply
  23. Carol T says:
    March 23, 2025

    This recipe just beat out my mom’s blackout cake as my new go to dark chocolate cake recipe (sorry, Mom)! This was delicious! I don’t have 4 pans the same size so I baked it in two 9×13 rectangular pans and cut each cake in half so I had four 9×6.5 layers. Worked great. My chocaholic son j(birthday boy) was over the moon with the flavors.

    Reply
  24. Charline Brand says:
    March 22, 2025

    Hello! Can I split the batter between 2-8” cake pans and use one of those cake leveler contraptions to torte the two cakes into four?

    Reply
    1. Michelle @ Sally's Baking says:
      March 23, 2025

      Hi Charline, we fear baking the batter in just two pans will cause it to rise and bake unevenly. What we’d do is still make the cake in four layers (or three layers as detailed in the recipe Notes), baking two layers at a time and leaving the remaining batter covered with a towel at room temperature. Once the two cake layers have baked, cooled, and been removed, you can proceed with baking the remaining batter. Hope this helps and that it’s a hit!

      Reply
  25. Susan says:
    March 20, 2025

    Good morning, I would love to make this cake for Easter, but I only have two 8 inck pans. Can I bake two layers and then the other two? Thank you,

    Reply
    1. Erin @ Sally's Baking says:
      March 20, 2025

      Hi Susan, certainly! You can bake two layers and keep the unused batter covered at room temperature until your cake pans are ready to be used again. Hope it’s a hit!

      Reply
  26. Ruopa says:
    March 17, 2025

    Mouth watering and a delicious cake.

    Reply
  27. Jenna says:
    March 15, 2025

    Does a fully assembled cake w the mousse filling freeze well?

    Reply
    1. Michelle @ Sally's Baking says:
      March 15, 2025

      Hi Jenna, Frosted cake freezes well, up to 3 months. See recipe notes for more details!

      Reply
  28. Petr says:
    March 14, 2025

    When I make a cake using the metric system and add 120ml of water, the batter becomes too runny. What should I do differently?

    Reply
    1. Lexi @ Sally's Baking says:
      March 14, 2025

      Hi Petr, how do the cakes bake up for you? This isn’t a thick batter—the video tutorial should give you a helpful visual of what the consistency should look like. Otherwise, is it possible that your flour or cocoa powder are under-measured?

      Reply
  29. Christina Shenefield says:
    March 14, 2025

    I want to make this into a 9 x 13 rectangular cake. Should I double the recipe? Should I change the cooking time or temperature? This is my favorite cake recipe!

    Reply
    1. Lexi @ Sally's Baking says:
      March 14, 2025

      Hi Christina, this batter as written bakes in about 40 minutes in a 9×13-inch cake pan. Same oven temperature. So glad it’s a favorite for you!

      Reply
  30. Ava says:
    March 13, 2025

    Hi Sally! I made this recipe vegan by using Bob’s Red Mill egg replacer, Trader Joe’s vegan heavy whipping cream, Kite Hill sour cream, and oat milk x white vinegar for buttermilk, and it came out fabulously! Ur recipes are seriously the BEST and are often easily made vegan 😀

    Reply