boozy bites brownies

guinness brownies with chocolate frosting

these Guinness brownies are super fudgy, full of rich chocolate flavor marked with a slight boozy smokiness. topped with a wonderfully sweet chocolate frosting, these brownies are absolutely drool worthy!

spring is practically knocking at the door. while I have several new spring recipes coming your way in the coming weeks, you can fully expect some fabulously decadent desserts to come first! st. patty’s day is coming soon. even if you don’t celebrate the holiday (I don’t really either), you should 100% jump on board with these Guinness brownies. well, Guinness brownies with chocolate frosting to be exact! these are quite literally the definition of fudge brownies. like, stay deliciously chewy for at least a week (in the fridge no less). so, throw a pack of stout in your cart, save the recipe and get ready for a truly decadent treat!

ok, but how would you describe these brownies?

I would describe these brownies as:
  • fudgy
    • technically not a word, but im making it one! you’ll find a pic of these next to the definition
  • deep, rich chocolate flavor
  • slightly boozy notes
  • smokiness from the stout
  • sweet, but just the right amount
    • these are brownies, okay!
  • moist for days
    • these STILL tasted fabulous a week later
    • no lie. I did it for recipe development purposes or these would have disappeared sooner!
Guinness brownies with chocolate frosting

ok, what do I need to get at the store?

these Guinness brownies with chocolate frosting are made from pantry staples. but, you will need:
  • guinness stout
    • or other stout you like!
  • unsalted butter
  • chocolate
    • this is the brand I use and like for this recipe
  • sugar
  • eggs
  • vanilla extract
  • dutch process cocoa powder
    • this has a smoother chocolate flavor
    • less acidic than regular unsweetened cocoa powder
  • espresso powder
    • optional, for a deeper chocolate flavor
  • salt
  • all purpose flour
  • powdered sugar
  • milk

from these ingredients you will make the brownies and the frosting!

do I need any special baking tools?

nothing too special! most of the recipe is made in one bowl! here’s what I used:
  • large mixing bowl
    • this will go in the microwave, so nothing metal!
  • silicone whisk and spatula
    • silicone tools are the easiest to make this recipe with
  • 9X9 metal pan
    • you can use an 8X8 but the baking time will be longer
  • medium sauce pan
    • this is to reduce the stout
  • stand or hand mixer fitted with paddle attachment or beaters
    • this is just to make the frosting

tips and tricks for the best brownies!

best subs for this recipe :
  • guinness: this is my personal favorite stout
    • use another malty stout if you have one you like!
  • chocolate: for this recipe, I used 2 (4oz) bars of 60% chocolate
    • use a 70-85 % for a more bitter, darker, coffee like flavor
    • stick with 60% for a classic sweet brownie flavor
    • it could be too sweet with a milk or semi sweet chocolate
  • espresso powder: optional, for boosting the flavor of the chocolate
    • omit if you don’t have
  • dutch process cocoa powder: this has the smoothest flavor and is best for this recipe
    • however, you can sub with a good quality unsweetened cocoa powder
guinness brownies with chocolate frosting
tips and tricks for this recipe:
  • you must reduce the beer:
    • this is the only way to get the flavor of the Guinness without the brownies turning into a cake!
    • it must be at least cool to the touch before using in the recipe
    • this also burns off the alcohol, while keeping the flavor of the beer
  • sift the dry ingredients:
    • for the cocoa and espresso powders, this releases more of the flavor
    • for the flour and powdered sugar, it breaks down any clumps
  • cutting the brownies:
    • these will be very fudgy
    • use a long knife to slice across the entire brownie if possible
      • wipe with a paper towel in-between cuts for the cleanest cut
    • make sure the brownies are completely cooled
      • you could even put them in the fridge for 30-60 minutes before cutting into them
  • frosting the brownies:
    • the frosting is optional, but is so, so good!
    • frost the brownies when they are completely cooled
    • use the back of a spoon to get the gorgeous swoops
  • storing the brownies:
    • once frosted, it’s best to keep the brownies in an airtight container in the fridge
    • if left unfrosted, they can be stored at room temperature in an airtight container

Guinness brownies with chocolate frosting
Guinness brownies with chocolate frosting
guinness brownies with chocolate frosting

Guinness brownies with chocolate frosting

these Guinness brownies are super fudgy, full of rich chocolate flavor marked with a slight boozy smokiness. topped with a wonderfully sweet chocolate frosting, these brownies are absolutely drool worthy!
5 from 2 votes
Prep Time 1 hr
Cook Time 35 mins
Cooling Time 30 mins
Total Time 2 hrs 5 mins
Course Celebrations, Dessert
Cuisine American


  • medium sauce pan
  • large mixing bowl
  • parchment paper
  • whisk and medium or large flexible spatula
  • stand with paddle attachment or hand mixer with beaters and mixing bowl
  • 9X9 metal baking pan


guinness brownies

  • 12 oz. bottle Extra Stout Guinness beer* (this will be reduced down to 2/3 c)
  • 1/2 c (113g) unsalted butter
  • 8oz. (226g) chocolate, roughly chopped use anything 60-70% cocoa (ie, bittersweet to dark)
  • 1 1/2 c (300g) granulated sugar
  • 1/2 c (118ml) reduced Guiness beer*
  • 2 (114g) large eggs, room temperature
  • 1 (17g) large egg yolk, room temperature
  • 1 tsp (5ml) vanilla extract
  • 1/4 c (20g) dutch process cocoa powder sub with unsweetened cocoa powder
  • 1 tsp espresso powder, sfited optional, but recommended
  • 1/2 tsp salt
  • 1 c (120g) all purpose flour

chocolate guinness frosting

  • 6 tbsp (85g) unsalted butter, room temperature
  • 1/2 c (40g) dutch process cocoa powder sub with unsweetened cocoa powder
  • 2-3 tbsp (30-45 ml) reduced Guinness beer* this should be the amount leftover
  • 1 tsp espresso powder
  • 2 tsp (10ml) vanilla extract
  • 1/8 tsp "pinch of salt"
  • 2 c (240g) powdered sugar, sifted
  • 1-2 tbsp (15-30 ml) milk, as needed


  • Pour a full 12oz. bottle of Guinness Extra Stout into a small or medium sauce pan. Bring the beer to a boil over medium heat. Heat the liquid until it reduces down to about 2/3 c, about 20-25 minutes.
    Remove from heat and cool until warm to touch, about 15-20 minutes. Do not use the reduced beer in the recipe until it has cooled a bit.
  • Preheat oven to 325 F / (165C) line pan with parchment paper, leaving 2" excess on at least two sides (for easy release).
  • In a large, microwaveable mixing bowl, place the butter and the chopped chocolate. Heat in the microwave in 30 seconds intervals, stirring each time, until the butter and chocolate have melted.
    Whisk in the sugar and 1/2 c of the reduced stout until very well combined.
    Whisk in the eggs, yolk and vanilla extract one at a time until each one is well combined before adding the next.
  • Sift the cocoa powder, espresso powder and salt directly into the wet ingredients. Whisk until smooth and very well combined.
    Sift in the flour. Switch to a soft/flexible spatula or spoon and stir the flour until just smooth and just combined.
  • Pour the brownie batter into the prepared pan. Bake at 350F / (165C) for 35-45 minutes or until the edges are set and a toothpick inserted into the center comes out with a few moist crumbs. Start checking around 30-35 minutes. If the toothpick comes out with wet batter, bake an addtional 3-5 minutes before checking again.
  • Cool brownies in the pan on a cooling rack for 30 minutes. Gently remove the brownies using the parchment overhangs to cool on a cooling until room temperature.
    Once cooled to room temperature, top with the chocolate guinness frosting, slice and enjoy!
  • chocolate guinness frosting:
    In a stand mixer fitted with the paddle attachment (or with hand mixer fitted with beaters), add the butter, cocoa powder, espresso powder, reduced guinness, vanilla extract and salt. Beat on medium speed until well combined. Add in the sifted powdered sugar and 1 tsbp of milk. Beat on low, increasing to high until the frosting is smooth, light and well combined. Add an additional tbsp of milk if needed.


this recipe was developed using Guinness Extra Stout beer. Any stout will work. just be sure you like the taste of the beer, as the flavor is concentrated and pronounced in the final product. 
brownies will be very fudge like after baking. allow them to completely cool before topping or slicing. unfrosted brownies can be stored in an airtight container at room temperature for about 4-5 days. once frosted, store brownies in an airtight container in the fridge for up to one week. these brownies will still taste delicious and not dried out even when stored in the fridge.
Keyword boozy desserts, brownies with frosting, fudgy brownies, guinness brownies
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