Guinness Chocolate Cake
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Rich, dark, and deeply chocolatey, this Guinness Chocolate Cake is the kind of dessert that feels special without trying too hard. The stout brings depth and moisture, the cocoa keeps things bold, and the Irish buttercream adds a smooth, lightly boozy finish. It’s festive enough for St. Patrick’s Day… and honestly perfect any day you want a chocolate cake that means business!!
Table of Contents
WHY YOU’LL LOVE CHOCOLATE CAKE WITH GUINNESS
- Deep chocolate flavor with real richness
- Ultra-moist, tender crumb
- Easy sheet-pan style cake… no layers required
- Buttercream is smooth, not cloying
- Feels celebratory without being fussy
Guinness Chocolate Cake
This is the cake people ask about. You set it on the counter, and someone always wants to know what’s in it.
Guinness chocolate cake with Baileys Irish Cream buttercream frosting is especially perfect for St. Patrick’s Day, but I don’t save it just for March.
If I’m craving a serious chocolate cake, one that’s rich and not overly sweet… this is the one I make.
The Guinness doesn’t shout. It just deepens everything and makes the chocolate taste more chocolatey.
But the frosting is where it really gets fun. Creamy, smooth, just enough Irish cream to notice without taking over. Slice it big, slice it small… it disappears either way. Holiday or not, this cake earns its spot on the table.
INGREDIENT NOTES
- Guinness Beer: Adds depth and moisture, not bitterness. Room temperature helps it blend smoothly.
- Cocoa Powder: Provides the backbone of the chocolate flavor. Use unsweetened natural cocoa for a classic taste, or Hershey’s Special Dark for something richer and a bit deeper.
- Sour Cream: Keeps the crumb tender and balanced. Full-fat is the way to go!
- Irish Cream Liqueur: Brings flavor and silkiness to the buttercream. Baileys is a classic for a reason, but any brand will do.
- Unsalted Butter: Used in both the chocolate Guinness cake and Irish cream frosting for richness and control.
VARIATIONS
No Alcohol: Use strong brewed coffee for the cake and milk or cream (or flavored coffee creamer!) in the frosting.
Richer Flavor: Include 1 teaspoon espresso powder in the cake batter.
Chocolate-On-Chocolate: Top chocolate Guinness cake with chocolate shavings.
Party Pan: Bake in a 9×13-inch pan for thinner slices, but adjust the bake time. Or double the recipe!
Cupcake Conversion: Divide the batter into a muffin tin (with paper liners) and bake for 17-20 minutes.
Holiday Style: Finish with festive sprinkles for St. Patrick’s Day.
SERVING SUGGESTIONS
- Great for potlucks and parties.
- Serve at room temperature for the best flavor.
- Drizzle caramel sauce over the frosting for an extra decadent treat.
- Pair chocolate cake with Guinness (yes, more!) or a coffee.
- Create a St. Paddy’s spread with Lucky Charms Treats or Leprechaun munch mix.
GUINNESS & CHOCOLATE CAKE FAQ
No. The stout is there to deepen the chocolate flavor, but the beer flavor doesn’t linger.
Yes. Bake the cake a day ahead, but add the frosting just before serving.
It’s balanced… enough for Irish cream flavor without feeling the effects. You can adjust the amount to taste.
The unfrosted cake freezes well, up to 2 months. Wrap in several layers of plastic wrap, then thaw in the refrigerator before making and adding the frosting.
This Guinness chocolate cake recipe works because stout and cocoa complement each other on a chemical level.
Guinness is slightly acidic and contains roasted malt compounds that intensify chocolate flavor without adding sweetness.
Heating the beer with butter helps dissolve cocoa solids evenly, creating a smooth base and preventing dryness. Sour cream adds fat and acidity, which tenderizes gluten and keeps the crumb soft.
Baking soda reacts with the acidic ingredients to give the cake lift without making it airy.
The buttercream relies on fat structure: softened butter traps air as it’s beaten, while powdered sugar stabilizes it.
Adding Irish cream introduces both liquid and alcohol, which thins the frosting slightly and enhances aroma without breaking the emulsion.
The result is a Guinness and chocolate cake that’s rich, moist, and structurally sound from edge to center.
DONNA’S PRO TIPS
- Let the Guinness-butter mixture cool slightly before mixing. We don’t want to scramble the eggs!
- Use room-temperature eggs and sour cream for a smooth batter.
- Don’t overbake. Pull it as soon as a toothpick comes out clean.
- Bring chilled cake to room temp before serving. The flavors taste better that way.
- Frost only after the cake is completely cool. Otherwise, it’ll melt into the surface.
TOOLS NEEDED
- 9×9-inch Baking Pan: Ideal thickness for even baking.
- Saucepan: For melting the butter and warming the stout.
- Mixing Bowls: Separate wet and dry mixtures to keep things smooth.
- Whisk & Spatula: This batter comes together easily by hand.
- Offset Spatula: Makes frosting Guinness chocolate cake clean and simple.
Enjoy!
With love, from our simple kitchen to yours.
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TL;DR (Too Long, Didn’t Read) THE QUICK VERSION
- Rich chocolate Guinness cake
- Moist, tender crumb
- Irish cream buttercream frosting
- Great for St. Patrick’s Day or anytime
- Easy sheet-pan dessert
- Alcohol-free swaps included
- Big chocolate flavor, zero fuss
Chocolate Guinness Cake with Irish Buttercream Frosting
Ingredients
Chocolate Guinness Cake
- 1 cup Guinness beer, room temperature
- 1 cup unsalted butter, cut into pieces
- 3/4 cup cocoa powder
- 2 cups granulated sugar
- 3/4 cup sour cream, room temperature
- 2 large eggs, room temperature
- 1 tablespoon pure vanilla extract
- 2 cups all-purpose flour
- 2 1/2 teaspoons baking soda
- 1/2 teaspoon kosher salt
Irish Buttercream Frosting
- 1 cup unsalted butter, softened
- 4 cups powdered sugar, sifted
- 2 to 4 tablespoons Irish cream liqueur, such as Baileys
- 1 teaspoon pure vanilla extract
Optional Toppings
- Caramel sauce
- Chocolate shavings
- Sprinkles
Instructions
- PREPARE OVEN: Preheat the oven to 350°F. Grease a 9 by 9-inch baking pan or line with parchment paper.
- HEAT STOUT: In a medium saucepan over medium heat, add 1 cup Guinness beer and 1 cup unsalted butter. Heat until the butter is fully melted.
- ADD COCOA: Whisk in ¾ cup cocoa powder until smooth. Remove from heat and let cool slightly.
- MIX DRY INGREDIENTS: In a large mixing bowl, whisk together 2 cups all-purpose flour, 2 cups granulated sugar, 2 ½ teaspoons baking soda, and ½ teaspoon kosher salt.
- MIX WET INGREDIENTS: In a separate bowl, whisk together ¾ cup sour cream, 2 eggs, and 1 tablespoon pure vanilla extract until smooth.
- COMBINE BATTER: Slowly whisk the Guinness mixture into the sour cream mixture. Pour the wet ingredients into the dry ingredients and stir until smooth and fully combined.
- BAKE: Pour the batter into the prepared pan and spread evenly. Bake for 35 to 40 minutes, until a toothpick inserted in the center comes out clean.
- COOL: Remove the cake from the oven and let cool completely in the pan.
- MAKE FROSTING: In a large mixing bowl, beat 1 cup softened unsalted butter until creamy. Gradually add 4 cups powdered sugar, mixing on low speed until combined.
- FLAVOR FROSTING: Add 2 tablespoons Irish cream liqueur and 1 teaspoon pure vanilla extract. Beat on medium speed until light and fluffy. Add additional Irish cream, 1 tablespoon at a time, until desired flavor and consistency are reached.
- FROST CAKE: Spread the buttercream evenly over the cooled cake.
- SERVE: Add optional toppings if desired. Slice and serve.
Donna’s Notes
Nutrition
All nutritional information is based on third party calculations and is only an estimate. Each recipe’s nutritional value will vary depending on the ingredients used, measuring methods, and portion sizes.
Originally published January 2026
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