Guinness Chocolate Brownies

I love making these Guinness chocolate brownies for my family when I crave a rich and fudgy chocolate dessert. Guinness beer, cocoa powder, and a silky chocolate ganache come together in just 35 minutes of bake time. The deep coffee like flavor makes them absolutely irresistible.

When I lived in New York, St. Patrick’s Day was always a big celebration with friends from all over the world. We would gather in tiny apartments and share dishes from our home countries alongside Irish classics, and those memories still warm my heart today. Now I celebrate at home with my family and a spread of my favorite St. Patrick’s recipes like my Guinness beef stew and a cozy bowl of Guinness French onion soup.

These Guinness chocolate brownies are always the star of the dessert table, and they are so easy to make. I start by mixing Guinness beer with oil, sugar, and vanilla, then fold in the cocoa and flour before baking for about 35 minutes. While the brownies cool, I make a simple chocolate ganache by melting chocolate chips with butter and a little beer, then whisking in powdered sugar until smooth. I love how the Guinness adds extra richness that regular brownies just can’t match, and I hope you give this one a try and enjoy it for St Patrick’s Day.

Why you will love this recipe

• Ready in under an hour: I love that these brownies bake in just 35 minutes and the ganache comes together in seconds. Minimal effort for maximum chocolatey results makes these perfect for busy weeknights or last minute celebrations.
• Rich coffee like flavor: The Guinness beer adds a deep and slightly malty taste that makes these brownies unique from any other recipe. I love how the beer enhances the chocolate without making the dessert taste like alcohol.
• Topped with silky ganache: I make the ganache with chocolate chips, butter, and a splash of Guinness for extra richness. The smooth chocolate layer on top takes these brownies from great to absolutely irresistible.
• Perfect for St. Patrick’s Day: I make a double batch every March because my family expects these on the dessert table now. They also make a great gift or dessert to bring to parties when I want an impressive treat that everyone will ask me about.

What you will need

Brownie: 

• Vegetable oil: I use vegetable oil for moisture, which helps create that fudgy texture I love in a brownie.
• Guinness stout beer: The star ingredient that gives these brownies their signature deep flavor.
• White sugar: Adds sweetness and helps create that shiny crackly top I always look for in a good brownie.
• Vanilla extract: Rounds out all the chocolate flavors.
• Salted butter: Melted and cooled, the butter adds richness and works together with the oil for the best texture.
• Eggs: Four large eggs give structure and richness to the batter.
• Flour: I use all purpose flour for a sturdy base that stays fudgy in the center.
• Unsweetened cocoa powder: I use dark cocoa powder for the deepest chocolate color and taste.

Ganache:

• Semisweet chocolate chips: They melt smoothly with butter and beer to create the silky topping I love.
• Salted butter: Adds richness and helps the ganache spread easily over the brownies.
• Guinness stout beer: A splash of beer in the ganache keeps the Guinness flavor consistent throughout the whole dessert.
• Powdered sugar: Sweetens and thickens the ganache to the perfect consistency for spreading.

How to make

Prep the pan: I preheat my oven to 350 degrees F and grease a 9×9 square baking pan. I line it with parchment paper so the handles stick up on two opposite sides for easy removal later.

Mix the wet ingredients: In a large bowl, I combine the oil, Guinness beer, sugar, and vanilla extract. I add the melted butter and mix until everything is well combined, then add the eggs and mix again.

Add the dry ingredients: In a medium bowl, I whisk together the flour and cocoa powder. I slowly add this mixture to the wet ingredients and stir until just combined. I try not to overmix so the brownies stay fudgy.

Bake the brownies: I pour the batter into the prepared pan and spread it evenly with a spatula. I bake for 35 minutes or until a toothpick comes out with just a few moist crumbs. I let the brownies cool completely in the pan.

Make the ganache: I place the chocolate chips, butter, and beer in a microwave safe bowl and heat in 30 second intervals, stirring between each until smooth. I whisk in the powdered sugar until silky and fully combined.

Top and chill: I pour the ganache over the cooled brownies and spread it into an even layer. I refrigerate until the ganache sets, then cut into bars and serve.

Expert tip

Let the Guinness come to room temperature

I recommend you to take the beer out of the fridge about 30 minutes before you start baking. Cold beer creates more foam and makes it harder to measure accurately. I also pour the beer into a small bowl first and let the foam settle before measuring. This gives me the right amount of liquid without air bubbles that could affect the texture of my brownies.

More tips to consider:

• I only beat the eggs until they just foam for the fudgiest brownies. Overbeating adds too much air and makes them cakey.
• I sift the cocoa powder and flour together to remove lumps and create a lighter batter that bakes evenly.
• I let the brownies cool completely before adding the ganache so the chocolate does not melt and slide off.
• I grease the pan and add parchment paper for the cleanest removal. The handles make it easy to lift the whole slab out at once.
• I taste the ganache before spreading it. If I want more sweetness, I add a bit more powdered sugar.

Recipe variations and add-ins:

• Espresso powder boost: I love adding 2 teaspoons of espresso powder to the batter for an even deeper coffee flavor. The espresso enhances the chocolate and Guinness without making the brownies taste like coffee.
• Brown sugar swap: I sometimes replace all or half of the white sugar with about 1 1/4 cups of packed brown sugar. The molasses adds a caramel note that my family loves.
• Nutty crunch topping: I sprinkle 1/2 cup of chopped walnuts or pecans on top of the ganache before it sets. The crunch adds great texture to each fudgy bite.
• Salted caramel drizzle: I drizzle 3 tablespoons of salted caramel sauce over the ganache for a sweet and salty combination. My kids ask for this version every time.
• Mint chocolate version: I add 1/2 teaspoon of peppermint extract to the ganache and top with crushed peppermint candies. This is perfect for the holidays!

Serving suggestions:

I love serving these brownies slightly warm with a scoop of whipped cream on the side. The cold cream against the fudgy chocolate is heavenly, especially when the ganache is still a little soft. For St. Patrick’s Day celebrations, I pair them with my baileys affogato for an adults only dessert spread, or I make a full Irish themed dinner with easy shepherd’s pie as the main course.

These brownies also make a great gift when I wrap them in cellophane with a festive ribbon. I bring them to potlucks and they always get recipe requests. For a fancier presentation, I cut them into smaller squares and serve on a tiered tray alongside my brownie baileys cheesecake and a batch of Irish mint brownies.

How to store leftovers:

• Store: I wrap individual brownies tightly in plastic wrap or store them in an airtight container at room temperature for up to 3 days. For longer storage, I keep them in the refrigerator where they stay fresh and moist for up to a week.
• Freeze: I wrap each brownie square in plastic wrap, then place them in a freezer safe bag or container. They stay fresh in the freezer for up to 3 months.
• Thaw: I transfer frozen brownies to the refrigerator overnight to thaw slowly. This keeps the texture fudgy and prevents the ganache from getting too soft.
• Reheat: I prefer to serve these at room temperature, but if I want them warm, I microwave individual squares for about 10 to 15 seconds.

Frequently asked questions

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