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Guinness brownies cut into squares with Guinness frosting

I asked readers about St. Patrick’s Day dessert recipe requests recently. The outpouring of “anything with Guinness” convinced me to pick up a 6 pack and begin recipe testing. My kitchen smelled like a brewery at 9am on a Tuesday morning, but the result was well worth my boozy wake up call.

Before you run away at the thought of beer brownies, let me explain. These Guinness brownies do NOT taste like beer. Guinness stout, with its roast coffee and caramelized flavors, is often paired with chocolate in baking. They’re a natural duo because Guinness not only intensifies chocolate, but adds a malty background.

A quick internet search for “Guinness brownies” will spew out a million results. Even still, I wanted to try my hand at this popular dessert because even though brownies seem pretty basic, it’s difficult to maintain a desirable texture when you begin adding all sorts of stuff. And I was ready for the challenge.

stack of 3 Guinness brownies

Guinness beer bottle



Dark chocolate comes to mind first. These Guinness brownies aren’t overly sweet, so you’ll find yourself grabbing another. (If it’s not the brownies that are addicting, it’s the frosting. More on that below!) If we’re talking texture, they’re very dense and very moist. In fact, they’re the moistest brownies I’ve ever baked… because they’re the only brownies I’ve ever baked with Guinness! Unlike my chewy fudgy homemade brownies, these Guinness brownies are not particularly chewy. They taste like fudge. A square of dark chocolate fudge.


To impart enough flavor into the brownies, we’d have to use a lot of beer. But adding liquid to brownies makes absolutely no sense. So let’s take what we learned from homemade strawberry cake and reduce the beer down on the stovetop first. The heat evaporates the liquid, but leaves the flavor. Little liquid, lots of flavor, won’t turn our brownies into cake. We also do this with champagne in mimosa cupcakes. And I do the same thing with my Guinness chocolate cupcakes, too!

This step is really easy and requires zero effort from you. Pour an entire 12 oz bottle of Guinness into a saucepan. (The whole bottle! Nothing to waste!) Leave it alone to simmer for 20ish minutes, until it’s reduced down to 2/3 cup. This is less than half the liquid we started with, but triple the flavor.

We’ll use 1/2 cup of reduced Guinness in the brownie batter and the remaining 2 and 1/2 Tablespoons in the frosting.

reduced Guinness in a glass measuring cup

The rest of the brownie ingredients are usual suspects. Butter, sugar, eggs, flour. Instead of cocoa powder, we’re using pure solid chocolate. Sometimes I use a combination of pure chocolate AND cocoa powder in homemade brownies, but I wanted to keep things really simple since we’re taking extra time to reduce beer on the stove.

Besides Guinness, you know what else intensifies chocolate’s flavor? Coffee. I add espresso powder to both the brownie batter and frosting on top. It’s optional, but if you really want a deep dark chocolate brownie, don’t leave the espresso powder out.

pouring brownie batter into baking pan


The brownies are great alone, but better with this frosting. Their decadent nature screams for something creamy! (That being said, eat one with a pint of Guinness in the other hand.)

This caramel colored frosting is an interesting flavor. Interesting in a good way! It’s mostly espresso flavored, though there are lingering notes of maple too. Not sure how it tastes like maple, but I suspect it’s the combination of reduced Guinness, vanilla, and confectioners’ sugar. Whatever the reason, it’s SO GOOD because it’s SO DIFFERENT.

Guinness brownies cut into squares with Guinness frosting

Guinness brownies cut into squares with Guinness frosting

You might also love my Baileys and coffee cupcakes and shamrock cookies too!

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Guinness brownies cut into squares with Guinness frosting

Guinness Brownies

  • Author: Sally
  • Prep Time: 45 minutes
  • Cook Time: 35 minutes
  • Total Time: 3 hours
  • Yield: 1620 brownies 1x
  • Category: Brownies
  • Method: Baking
  • Cuisine: American


These Guinness brownies are made from reduced Guinness Stout. They’re fudgy, rich, and topped with espresso powder and Guinness infused frosting!


  • one 12-ounce bottle Guinness Extra Stout
  • 3/4 cup (12 Tbsp; 175g) unsalted butter
  • two 4-ounce bars (226g) semi-sweet chocolate, coarsely chopped*
  • 1 and 1/4 cups (250g) granulated sugar
  • 3 large eggs
  • 1 teaspoon pure vanilla extract
  • 1 cup (125g) all-purpose flour (spoon & leveled)
  • 1/2 teaspoon salt
  • optional: 1/2 teaspoon espresso powder

Guinness Frosting

  • 1/2 cup (1 stick; 115g) unsalted butter, softened to room temperature
  • 2 cups (240g) confectioners’ sugar
  • 23 Tablespoons reduced Guinness (from step 1)
  • 1 teaspoon espresso powder
  • 1/2 teaspoon pure vanilla extract
  • 1/4 teaspoon salt


  1. 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, about 20-22 minutes. Set aside to cool for at least 10 minutes. You will use 1/2 cup in the brownies and the rest in the frosting.
  2. Preheat the oven to 350°F (177°C) and grease a 9×9 inch 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.
  3. 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 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.
  4. Bake for 32 minutes, then test the brownies with a toothpick. Insert it into the center of the pan. If it comes out with wet batter, the brownies are not done. 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.
  5. Remove from the oven and place on a wire rack to cool completely before frosting or cutting into squares.
  6. 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, add a splash of milk.
  7. Frost cooled brownies.
  8. Cover and store leftover brownies at room temperature for up to 1 week.


  1. Make Ahead Instructions: Freeze frosted or unfrosted brownies up to 3 months. Thaw overnight in the refrigerator then bring to room temperature before serving.
  2. Special Tools: KitchenAid Hand Mixer | Glass Mixing Bowls | Saucepan | 9×9 Baking Pan | Icing Spatula
  3. Chocolate: You can find 4 ounce chocolate baking bars in the baking aisle. I like using Ghirardelli or Baker’s brand. You can use 8 ounces (heaping 1 and 1/3 cups) of quality chocolate chips instead, such as Ghirardelli brand.

Keywords: Guinness brownies

Reader Questions and Reviews

  1. 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!!!!

  2. 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

    1. 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!

  3. 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!

    1. 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.

  4. 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!

    1. 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!

  5. Any suggestions for making these in a 9 x 13 pan for a crowd? Doubling or not quite? Thanks!

    1. Hi Cindy! You can double this recipe for a 9×13 inch pan. I’m unsure of the exact bake time.

  6. 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!

  7. 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!

  8. Probably a stupid question, but…Are these kid friendly and pregnant friendly?

    1. 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.

      1. 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.

  9. 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.

  10. 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?

    1. 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!

  11. 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.

  12. 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!

  13. 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!

    1. 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!

  14. 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.

  15. 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!

  16. 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!

  17. 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!

  18. So I reduced it too much … only 1/3 instead of 2/3 cup remains. What do you suggest?

    1. 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.

  19. Absolutely the best brownies I’ve ever had! will definitely make these again and again!

  20. 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?

  21. 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.

  22. 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?

    1. 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.

  23. 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.

  24. 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

    1. 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!

  25. 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!

  26. 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!

  27. 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.

    1. 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.

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