If you love rich chocolate desserts, these Guinness brownies are about to become your new favorite. They’re deeply fudgy, intensely chocolatey, and topped with a creamy Guinness-infused frosting. I promise you don’t have to like beer to love these St. Patrick’s Day-perfect brownies!
I originally published this recipe in 2018, and I’ve since updated it with new photos and extra success tips for consistently excellent results.
Before you worry—these brownies do not taste like beer. Instead, Guinness stout enhances the chocolate flavor with roasted, coffee-like notes and a hint of caramel sweetness. It’s the same reason stout is often paired with chocolate desserts, such as this Guinness chocolate cake. The flavors naturally complement each other.
These Guinness brownies are decadent and deeply chocolatey, but not overly sweet. A chocolate dessert for a grownup palate!
- Texture: dense, moist, and fudgy
- Flavor: dark chocolate with roasted malt notes
- Frosting: creamy, with hints of espresso and caramel
Why You’ll Love These Guinness Brownies
These brownies stand out from typical chocolate brownies because of their deep, complex flavor and ultra-fudgy texture.
Here’s what makes them special:
- Complex chocolate flavor: Guinness stout intensifies the pure melted chocolate with its roasted, coffee-like notes.
- Ultra-fudgy texture: Close in texture to my seriously fudgy homemade brownies.
- Creamy Guinness frosting: Light, smooth, and slightly espresso-forward with subtle malty caramel notes.
- A wonderful dessert recipe for St. Patrick’s Day… or anytime you’re craving a rich chocolate dessert!
What Does Guinness Add to Brownies?
Dark, smooth, and creamy, Guinness stout contains roasted barley, which contributes flavors similar to roast coffee, cocoa, and caramel. Guinness is often used in baking and almost always paired with chocolate. The two work well together because Guinness, like coffee, intensifies chocolate’s natural flavor.
- Have you ever had this chocolate cake with hot coffee in the batter before? It’s just like that.
Truly, you don’t have to like beer to love desserts made with Guinness! Desserts like my Guinness cupcakes don’t taste like beer. Rather, they have a more complex chocolate flavor with a malty background.
Reducing the beer first intensifies these flavors while preventing excess liquid in the batter. We take that same first step in this recipe for Guinness chocolate cake. More on this below!
Other Ingredients You Need
Besides a bottle of Guinness, the rest of the ingredients are all pretty typical brownie staples:
- Butter: You can make brownies with butter, oil, or both; but in testing, we liked these brownies best with all butter.
- Chocolate: Use 8 ounces (2 standard baking bars) of semi-sweet or bittersweet chocolate. Since this is the only chocolate in these Guinness brownies, use a good-quality brand—I typically use Ghirardelli brand.
- Sugar: Sugar does more than sweeten brownies. As the batter bakes, it liquifies to create a softer center and rises to the top, forming that shiny, crackly surface.
- Eggs: Eggs bind, add richness, tenderize, and provide structure. This recipe uses 3 eggs for a tight crumb and melt-in-your-mouth texture.
- Flour: More flour makes cakier brownies. For dense, fudgy brownies, you only need 1 cup.
- Salt & Vanilla: To balance all the flavors.
- Espresso Powder: Optional, but I recommend it for a deeper chocolate flavor. It’s added to both the brownie batter and frosting. You can find espresso powder in the baking or coffee aisle at the grocery store or online.
- Confectioners’ Sugar: For sweetening the frosting.
Why is there no baking powder or baking soda in these brownies? Adding baking powder or baking soda lifts brownies up and creates a cakier result. But today, we want a brownie so dense and fudgy that it’s basically 1 step up from eating pure chocolate—just like these seriously fudgy homemade brownies.
The Key Step: Reduce the Guinness
The secret to bold Guinness flavor in your brownies without ruining their texture is reducing the beer first. Simmering the beer concentrates its flavor while preventing excess liquid in the batter, so the brownies stay dense, moist, and perfectly fudgy instead of cakey.
By reducing a full bottle of Guinness on the stovetop, the water evaporates while the flavor intensifies. The result: malty stout flavor without compromising the brownie texture.
Here’s the process:
- Pour one bottle (or can) of Guinness stout into a saucepan.
- Let it simmer until it reduces to about 2/3 cup (takes about 20 minutes, totally hands off). This is less than half the liquid we started with, but triple the flavor.
- Let it cool slightly. Or reduce the Guinness in advance, and refrigerate until you’re ready to make the brownies.
This technique is similar to reducing fruit or champagne for baking—less liquid, more flavor. We do the same thing to concentrate strawberry flavor for strawberry cake, apple cider flavor for apple cider donuts, and champagne for champagne cake roll.
We’ll use 1/2 cup (120g/ml) of reduced Guinness in the brownie batter, and the remaining 2 and 1/2 Tablespoons (40g/ml) in the frosting.
How to Make the Best Guinness Brownies
Once you’ve reduced the Guinness, the batter comes together quickly.
Melt the butter and chocolate together to create a smooth base for these dense, fudgy brownies. It helps to cut the butter into pieces so it melts evenly. You can use the microwave or stovetop. Whisk in the sugar and the reduced Guinness, then the eggs and vanilla, and finally the dry ingredients. The batter will be thick and shiny.
Spread it into a lined 9-inch square metal baking pan (not glass or ceramic) so the brownies bake evenly.
Guinness Frosting
The brownies are fantastic on their own, but their decadent nature begs for something creamy. While you could enjoy a creamy pint of Guinness alongside these brownies, I prefer topping them with this Guinness frosting instead!
It’s creamy, lightly sweet, and flavored with more of the reduced Guinness, espresso powder, and vanilla.
The flavor is hard to describe but completely delicious—espresso-like with subtle malty, caramelized notes from the stout.
These Guinness brownies would also be fantastic topped with vanilla ice cream, homemade whipped cream, or the mocha whipped cream from my flourless chocolate cake recipe.
No. Guinness brownies do not taste strongly like beer. Instead, the stout enhances the chocolate flavor with subtle roasted notes similar to coffee or dark caramel. The result is a richer, deeper chocolate brownie rather than a beer-flavored dessert.
Classic Guinness Draught stout works best for baking brownies. It has a smooth, slightly roasted flavor that complements chocolate. Extra stout or other dark stouts can also work, but they may produce a slightly stronger malt flavor.
No. Reducing Guinness concentrates its flavor while removing excess liquid. Brownie batter can easily become too thin if extra liquid is added, which can lead to cakey or gummy brownies. Simmering the stout first ensures the brownies stay dense, moist, and fudgy.
Yes. Although the brownies contain Guinness, the alcohol content is reduced during simmering and baking. If you prefer an alcohol-free version, you can substitute a stout-style nonalcoholic beer for a similar flavor.
Brownies are done when a toothpick inserted in the center comes out with a few moist crumbs—not coated in wet batter (underbaked), and not completely clean (overbaked). Overbaking can make brownies dry, so it’s best to remove them from the oven when the center is just set.
Guinness Brownies
- Prep Time: 45 minutes
- Cook Time: 35 minutes
- Total Time: 3 hours
- Yield: 16-20 brownies
- Category: Brownies
- Method: Baking
- Cuisine: American
Description
These Guinness brownies are made from reduced Guinness Stout. They’re fudgy, rich, and topped with espresso- and Guinness-infused frosting!
Ingredients
- one (11.2–12-ounce (330–355ml) bottle Guinness Draught Stout beer
- 3/4 cup (12 Tbsp; 170g) unsalted butter
- two 4-ounce bars (226g) semi-sweet chocolate, coarsely chopped*
- 1 and 1/4 cups (250g) granulated sugar
- 3 large eggs, at room temperature
- 1 teaspoon pure vanilla extract
- 1 cup (125g) all-purpose flour (spooned & leveled)
- 1/2 teaspoon salt
- optional: 1/2 teaspoon espresso powder
Guinness Frosting
- 1/2 cup (8 Tbsp; 113g) unsalted butter, softened to room temperature
- 2 cups (240g) confectioners’ sugar
- 2–3 Tablespoons reduced Guinness (from step 1)
- 1 teaspoon espresso powder
- 1/2 teaspoon pure vanilla extract
- 1/4 teaspoon salt
Instructions
- In a small saucepan, bring the Guinness to a boil over medium-high heat. Once boiling, reduce to medium heat and allow to simmer until reduced down to 2/3 cup (160g/ml), about 12–15 minutes. Set aside to cool for at least 10 minutes. You will use 1/2 cup (120g/ml) in the brownies and the rest in the frosting.
- Preheat the oven to 350°F (177°C) and grease a 9-inch square baking pan or line with aluminum foil or parchment paper, leaving an overhang on the sides to lift the finished brownies out (makes cutting easier!). Set aside.
- Place the butter and chopped chocolate in a large microwave-safe bowl. Melt in 30-second increments, whisking after each, until completely smooth. Whisk in the sugar and 1/2 cup (120g/ml) of reduced Guinness until completely combined. Whisk in the eggs and vanilla extract. Finally, whisk in the flour, salt, and espresso powder (if using). The batter will be thick and shiny. Pour/spread evenly into prepared pan.
- Bake for 32 minutes, then test the brownies with a toothpick. Insert it into the center of the pan. If it comes out coated with wet batter, the brownies need more time. If there are only a few moist crumbs, the brownies are done. Keep checking every 2 minutes until you have moist crumbs. My brownies take about 35 minutes.
- Remove from the oven and place on a cooling rack to cool completely in the pan before frosting or cutting.
- Make the frosting: In a large bowl using a handheld or stand mixer fitted with a whisk attachment, beat the butter on high speed until completely smooth and creamy, about 2–3 minutes. Add the confectioners’ sugar, beating on low at first then increasing to high speed. Once creamy and combined, beat in 2 Tablespoons of reduced Guinness, the espresso powder, vanilla extract, and salt. Taste. Add the remaining reduced Guinness if needed. If you want the frosting a little thinner, beat in a splash of milk.
- When cool, lift the brownies out by gripping the parchment overhangs and transfer to a cutting board. Spread frosting over cooled brownies. Use a sharp knife to cut into squares.
- Cover and store leftover brownies at room temperature for up to 1 week.
Notes
- Make Ahead Instructions: Freeze frosted or unfrosted brownies up to 3 months. Thaw overnight in the refrigerator then bring to room temperature before serving.
- Special Tools (affiliate links): Electric Mixer (Handheld or Stand) | Glass Mixing Bowls | Whisk | Saucepan | 9-inch Square Baking Pan | Icing Spatula
- Chocolate: You can find 4 ounce chocolate baking bars in the baking aisle. I like using Ghirardelli brand or Baker’s brand. You can use 8 ounces (heaping 1 and 1/3 cups) of quality chocolate chips instead, such as Ghirardelli brand.
Reader Comments and Reviews
I’d like to double this recipe and I’m wondering if I can use a 9×13 or if I need to bake in 2 pans. Want to make sure the brownies are Dunne I the center and not dried out on edges.
Hi Becky, you can absolutely try doubling this recipe for a 9×13 pan. We’re unsure of the exact bake time — use a toothpick to test for doneness. If there are only a few moist crumbs, the brownies are done.
These are WONDERFUL! All the flavors in this recipe balance very well! These are now a St.Patrick’s Day tradition in my house, I’ve made them two years in a row to rave reviews!
Sally!
I have made a very old recipe for brownies for MANY years. I decided this would be fun to try so I did. OMG!!
I sent these with husband for poker night and the guys called me to praise!
Soooo good & I have a new go-to for brownies!
Thank you for all you do!
How do you make these more cake-like instead of fudgy?
Hi Victoria, the addition of baking powder would certainly lift the crumb to yield a cakey Guinness brownie, but it would take some recipe testing on our end to give you a confident suggestion on how much. If you do give anything a try, we’d love to know how it turns out for you. Or, you might enjoy our Guinness Cupcakes instead!
Hi there,
Would you recommend any other type of frosting? I’m not a fan of coffee (even though I like Guinness lol). Or could I leave the espresso out of it?
Thank you x
Hi Siobhan, you could certainly omit the espresso from this frosting recipe, or try the frosting from our chewy fudgy homemade brownies. Happy baking!
Honestly I couldn’t taste the Guinness. Also, there is way too much butter in these. If I ever remake them I would just reduce it to at most one stick.
Does the order in step 3 matter? Instead of “sugar and guinness, then eggs and vanilla, then flour, salt and espresso” can you just put in other ingredients while you are waiting for the guinness to cool?
Thanks
Hi Emma, It’s best to add all of the liquid ingredients together first, and then once they are fully combined add the dry ingredients. You can certainly mix the flour, salt, and espresso powder together in a separate bowl ahead of time to have it ready to add to the wet ingredients.
Hi Sally,
I am making these for my boyfriend but I was wondering what it would change if I used the regular Guinness and not the extra stout? Since I wouldn’t be using a whole 6 pack, I prefer to buy the normal one as he won’t drink the extra stout.
Thanks
No changes necessary!
Hi Sally,
Your website is now my go to for everything!!
I love all your recipes and absolutely everything I have made from your website has been adored by all my friend and family..
you’re my new secret weapon!
I actually feel bad taking credit for your amazing concoctions!!
Brownies were a big hit!
Perfect isolation food
Love to you! ♥️
Can we post pictures?
So glad you enjoyed the Guinness Brownies! Feel free to email me your recipe photos 🙂 sally@sallysbakingaddiction.com
Absolutely the best brownies I’ve ever had! will definitely make these again and again!
So I reduced it too much … only 1/3 instead of 2/3 cup remains. What do you suggest?
Hi HC! You need 1/2 cup of the brownies, so I would add another 3 Tablespoons to yield 1/2 cup of regular Guinness unless you want to reduce more down.
Holy cow these are good! I used an 8in pan and they are so moist and flavorful and fudgy. Yum! I wasn’t totally in love with the frosting but mostly because I’m not a frosting on brownies type of person, and if I did the frosting again I would probably use peanut butter whiskey instead of the beer. Just for fun!
Deliciously fudgy brownies with a nice light frosting. You get hints of the Guinness throughout and the espresso powder is a good add. Perfect for St. Patrick’s Day!
These brownies were SO, SO good! I made them for an early St. Pat’s dinner and they were a big hit. Gotta make the frosting–it’s great and a big part of the overall flavor. I loved the addition of the espresso powder. I want to try the cupcakes next. Thanks for a great recipe!
Oh my goodness!!! That frosting is heavenly – this is the perfect antidote to these scary times! Thank you, Sally, for a most amazing recipe. No brownie will ever come close.
Sally, I’m at altitude here, about 6,000′ & would recommend more than 12 oz of beer at the start. I, myself, would use 20 oz. of beer next time. After the 20 – 22 mins. of simmering, I was down to 1/2 c. of Guinness. Also, I put aside the 2 T. for the icing, but it seemed to evaporate to less & so I just mixed up some of the espresso & water to substitute. I used one of the fat piping tips that someone gave me & piped 16 rosettes on each square & sprinkled with green sprinkles, so they look great! Thanks!
Wanted to say I’m getting lots of kudos on these brownies! They taste great & my friends are saying, “the best ever”! Icing is awesome!! Thanks for a great recipe, Sally!
So delicious and quite easy to make. I was able to get 24 brownies out of a 9×9 pan as they were very rich. My friends loved them!
Made these brownies yesterday and just finished frosting them. Oh these are so good! Fudgie and dense, full of chocolate flavor. The frosting is fabulous. Love the condensed Guinness stout flavor in the frosting. It goes so we’ll with the brownies.
Sally I cant wait to try these! Is there a simple way to know (for this and other reductions, generally) when the volume is reduced to 2/3 cup? Do you have to keep pouring it out to measure, then back to saucepan?
Yes, honestly the best way is to pour it into a glass measuring cup to check. After the first time you will have a better idea about how long your particular oven/pot takes so it does get easier!
Sally, I have reviewed this recipe previously, it is, hands down, the absolute best brownies in the entire world LOL!!! They are easy to make and the taste is first rate with the melding of the expresso power, beer, etc. We do a lot of entertaining and this is by far the most requested dessert!! Keep up the good work.
Probably a stupid question, but…Are these kid friendly and pregnant friendly?
Hi Cathy, the alcohol is cooked out when the Guinness is reduced on the stove, so these are perfectly fine for older kids– however I wouldn’t personally serve these to my toddler or anyone abstaining from alcohol. Feel free to make the best decision based on who you are serving these to.
I have loved every recipe of yours I have tried (I’ve lost count of how many)! I cannot get my hands of bottles of the Guinness stout, would a can of Guinness draught stout work or would the flavour profile be different? I want to make the cupcakes as well for St. Patrick’s Day along with a Guinness wheaten bread recipe I got when I was in Ireland.
Any Guinness works!
Absolutely the BEST brownies I’ve ever made! The reduced Guinness and the espresso powder added a depth of flavor most brownies are missing and I liked that they weren’t overly sweet. Thank you Sally, keep up the good work!
Hi Sally!
I just made these again this weekend–I’m not sure if I’ve commented on them before, but I don’t think I have. I made them for a reception in mini-cupcake pans so that I didn’t have to worry about cutting them up for a crowd. They are SO GOOD. For a number of years I made something called “Chocolate Stout Cupcakes” that appeared on a couple of big sites, and while they were okay I never felt that they had much depth of flavor and I also thought they were a little dry. Then I found your recipe–genius! Reducing the beer is such a great idea. I’ve made these with Young’s Double Chocolate Stout and this past time with an Irish Stout. Young’s comes in a 14-oz. can and the Irish stuff in a 13-oz. one, so even more beer flavor!
Any suggestions for making these in a 9 x 13 pan for a crowd? Doubling or not quite? Thanks!
Hi Cindy! You can double this recipe for a 9×13 inch pan. I’m unsure of the exact bake time.
How long did you bake for when you doubled it?
Do you think these brownies have the right texture to crumble up in a trifle?
Absolutely!
Hi Sally,
I work at a brewery so I’m always looking to incorporate interesting beers into baking. I have with me a maple and pecan stout which screams out brownies. If I added actual pecans and a little maple into the batter to enhance the flavour, would you recommend balancing the moisture with just a tad more flour? Or would the extra sweetness in the maple need a tad less sugar too?
This looks a great recipe so I’ll have an experiment anyway and see how it goes!
That sounds delish! You can absolutely reduce that beer the same way and add chopped pecans to the brownies. For a stronger maple flavor you can add maple extract without having to alter the other ingredients. Let me know what you try!
Can you substitute instant coffee for espresso powder?
Hi Lauren! You can, yes, but instant coffee powder isn’t quite as strong as espresso powder. You can increase the amount or simply expect a milder flavor.
I LOVE these brownies and look forward to them all year (it’s almost that time again!). I have to restrict them to St. Patrick’s Day or else I’ll be making them every weekend because they are pretty easy and SO good. My mom used to make these for our family, and when I moved out it was one of the recipes I requested from her – huge hit every year!
Hi Sally, is the frosting of the consistency to pipe and if so what tips would you recommend? Thinking if adding the frosting to chocolate cupcakes
This frosting will a bit thinner than my vanilla buttercream. It’s perfect to use for writing on the brownies (with a #2, #3 or #4 tip) but if you want it to hold a more intricate shape on cupcakes you can add more confectioners sugar to make it thicker. I have a post with all of my favorite piping tips and video!
Made these for a family gathering…..everyone loved them! Perfect consistency, and you can just taste a hint of the stout, but not overpowering….I used espresso powder too, and it really enhanced the flavor. BIG hit. Many wanted copies of recipe. Will definitely add to “go to” binder!!!!