Tessa’s Recipe Rundown
Taste: Chocolate heaven, with light, almost coffee-like notes from the Guinness, and a sweet Irish cream frosting, topped off with more chocolate decadence from the ganache.
Texture: The cake is moist and fudgy, while the frosting is lusciously smooth and creamy.
Ease: The cake batter is super easy, and so is the frosting and ganache. Assembly may seem daunting, but I promise it’s easier than it seems.
Pros: The perfect dessert for St. Patrick’s Day, or any birthday.
Cons: There are a few components to this cake, but they’re all totally worth it, promise!
Would I make this again? Yes, 100%
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This Guinness Chocolate Cake with Irish Buttercream recipe involves chocolate AND booze. It doesn’t get much better than that!
What better way to celebrate St. Patrick’s Day? Or just any day, really. Because some days require chocolate and Bailey’s. And that might be because you’re celebrating something great… or because it’s been a long day.
The chocolate cake component of this recipe is super simple. You don’t even need an electric mixer for the cake batter! So you only have to clean your stand mixer bowl once (for the frosting).
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The cake base contains sour cream to give the cake a ton of richness and moisture, and the Guinness stout beer gives it a deep, roasted, slightly coffee-like taste that pairs so wonderfully with that rich chocolate flavor.
Feel free to get creative with decorating this cake! We went for a ‘naked’ look where the sides of the cake peek through the frosting. That focuses the attention on that beautiful chocolate ganache drip topping. You could go crazy with green food coloring, shamrock sprinkles, or gold coins for a fun, festive look.
Or keep it classic with chocolate shavings or even a drizzle of salted caramel for an extra tasty garnish.
Sprinkle of Science
How to Make Guinness Chocolate Cake with Irish Buttercream
How to Make MOIST Chocolate Cake
Be very careful not to accidentally over-measure the flour and cocoa powder in this recipe. This will lead to dense, dry, or tough cake. The best way to ensure this never happens is to measure your ingredients by weight using a digital kitchen scale. This will forever improve your baking! If you don’t have a scale, be sure to use the spoon and level method to measure your dry ingredients.
How to Prevent Your Chocolate Cake from Sinking
This is an extremely moist and rich cake recipe, so if your cake does sink slightly in the center don’t worry. It’s definitely not ruined! Simply use a serrated knife or cake leveler to level off the cake for a flat layer. To prevent your Guinness Chocolate Cake from sinking in the first place, check out my tips below:
- Make sure your oven is at the correct temperature. Many home ovens actually run much hotter or colder than they say. Learn more about home ovens here.
- Check that your baking powder & soda are fresh. These leavening agents are crucial to helping your cake rise, and can actually lose their effectiveness long before the date printed on the packaging. More on baking soda and baking powder here.
- Be sure to measure all ingredients properly. As mentioned above, I love my digital kitchen scale to ensure precision! Learn more about weighing ingredients here.
- Avoid over-mixing the batter. Over-mixing the batter can make your cake tough and rubbery and cause it to sink.
- Bake the batter soon after mixing it up. Don’t let the batter sit for any longer than necessary before baking, as this can cause the leavening agents to lose their effectiveness, and your cake may sink, or it may never rise in the first place!
- Bake in the center of your oven and don’t open the oven door unnecessarily, to ensure your oven maintains the most even heat possible.
- Don’t underbake the cake. A cake tester or toothpick should come out clean!
- More tips for how to prevent cakes and loaves from sinking in this article.
What Cake Pan do I Need for This Cake?
This Guinness Chocolate Cake with Irish Buttercream recipe was written to use two 8-inch pans. These Fat Daddios pans are my favorites. Be sure to use pans that are deep enough (I recommend 3 inches) to avoid your cake spilling over.
Can I Bake This with Different Sized Baking Pans?
Probably! You’ll just need to do a little math to adjust the timing and calculate the volume. Check out Wilton’s handy guide for converting cake baking pans.
Can you Bake This Cake into Cupcakes?
Almost any cake recipe can be made into cupcakes. Check out my full guide on how to convert cake into cupcakes (and vice versa!).
Tips for Perfect Bailey’s Irish Cream Buttercream
- Butter temperature. Be sure your butter is at a cool room temperature, about 67°F, so it blends into a smooth buttercream icing.
- Use finely ground powdered sugar. Not sure if you’ve got the right sugar? Check out my post on 6 Secrets to Perfect Buttercream.
- Whatever you do, don’t skip sifting the sugar! If you skip sifting your powdered sugar, you will end up with unattractive lumps and bumps in your iced cake.
- Irish Cream substitutes. If you’d prefer to keep this recipe free of any un-cooked alcohol, feel free to replace the Irish Cream with regular heavy cream.
How to Make the Perfect Chocolate Ganache Drip
There are a few ways to make your ganache drip, but here’s how I like to do it:
- Firstly, be sure your cake is cold. Allow it to chill in the refrigerator until the buttercream is chilled and firm to the touch before applying the ganache drip.
- Also, be sure that your ganache isn’t too hot, as this will melt the buttercream and run straight off the cake. Test the consistency of the drip by pouring a tiny bit down the side of a glass.
- Place the cake on a cake turntable, so you can easily turn the cake as needed. This is especially helpful when applying the drips down the sides of the cake.
- Carefully pour some of the ganache over the top of the chilled cake. Use an offset spatula to quickly smooth the ganache over the top of the cake before it sets, spreading evenly just to the cake’s edge.
- Use a squeeze bottle to gently squeeze one drip at a time down the sides of the cake.
- Before the ganache fully sets, add sprinkles, chocolate curls, or any other decor you like. It won’t adhere properly if you allow the ganache to firm up before adding.
How to Make Guinness Chocolate Cake Ahead of Time
You can wrap unfrosted, un-cut, cooled cake layers completely in several layers of plastic wrap. Place inside a freezer bag. Store at room temperature for up to 4 days or freeze for up to 2 months. Defrost overnight in the fridge (do not defrost at room temperature or you will end up with mushy cake).
How to Store Guinness Chocolate Cake with Irish Buttercream
Since frosting acts as a protective seal that keeps the cake moist and fresh, frosted cakes can be stored at a cool, dry room temperature for 2 to 3 days. Especially this frosting, since it has some alcohol content to further preserve. Cover with a cake keeper to keep the frosting and decorating intact. Don’t use plastic wrap, which will not only ruin your frosting, but also create condensation that can cause the frosting to separate.
More Chocolate Cake Recipes
- Best Chocolate Cake
- Nutella Cake
- Chocolate Zucchini Cake
- Chocolate Bundt Cake
- Chocolate Mint Cupcakes
More St. Patrick’s Day Recipes
- Chocolate Peanut Butter Whiskey Truffles
- Frozen Mint Chocolate Chip Pie
- Bailey’s Cheesecake Bars
- Mint Chocolate Whoopie Pies
Find ALL my St. Patrick’s Day recipes here!
Guinness Chocolate Cake with Irish Buttercream
Ingredients
For the Guinness Chocolate cake:
- 1 3/4 cups (222 grams) all-purpose flour
- 2 cups (400 grams) granulated sugar
- 3/4 cup (64 grams) unsweetened cocoa powder
- 2 teaspoons baking soda
- 1/2 teaspoon baking powder
- 1 teaspoon fine salt
- 3/4 cup (170 grams) sour cream or plain full-fat yogurt, at room temperature
- 1/2 cup fresh vegetable oil
- 3 large eggs, at room temperature
- 1 teaspoon vanilla extract
- 1 cup Guinness beer
For the Irish Buttercream:
- 4 sticks (454 grams) unsalted butter, at cool room temperature
- 6 cups (750 grams) powdered sugar, sifted
- 1/4 cup plus 2 tablespoons Irish cream, such as Bailey’s
For the Chocolate Drip:
- 4 ounces (113 grams) semisweet or bittersweet chocolate, finely chopped
- 1/2 cup heavy cream
- sprinkles or chocolate curls for topping, optional
Instructions
Make the cake:
- Preheat the oven to 350°F. Generously grease two 8-inch wide x 3-inch deep cake pans and line with parchment paper rounds.
- In a large mixing bowl, whisk together the flour, sugar, cocoa, baking soda, baking powder, and salt.
- In a medium bowl, whisk together the sour cream, vegetable oil, eggs, vanilla, and beer.
- Add the wet ingredients into the dry ingredients and stir with a spatula until just combined, being careful not to overmix.
- Divide the batter between the prepared pans and bake for 35 to 40 minutes, or until a cake tester comes out clean. Cool the cakes in their pans for 30 minutes before carefully turning them out onto a cooling rack or wire rack to cool completely. If possible, freeze the cakes while you prepare the buttercream.
Make the buttercream:
- In a large bowl, use an electric mixer or hand mixer to beat the butter until light and fluffy. Gradually add the sifted powdered sugar, then the Irish cream. Beat the mixture on high speed until very light, fluffy, and smooth, about 3 minutes. If the frosting is too thick, add a splash more Irish cream. If it’s too thin, add more powdered sugar.
Assemble:
- Place one cake layer on a cake stand or serving plate. Frost the top of the cake generously, as this will become the filling. Use even more if you're decorating as a 'naked' cake as shown in the photos. Top with the other cake layer, flat side up.
- With an offset spatula, spread a very thin layer of frosting all over the cake. This layer is a crumb coat and should act like spackle. For the smoothest frosting, return the cake to the fridge or freezer until firm to the touch.
- Spread the remaining frosting all over the cake. If desired, focus the frosting on the top to maintain the 'naked' look. Refrigerate while you prepare chocolate drip.
Make chocolate drip:
- Place the chopped chocolate in a heatproof bowl. In a small pan, bring the heavy cream to a simmer then immediately remove from heat and pour over chocolate. You can also do this in the microwave. Cover for a few minutes then stir until smooth.
- Allow to cool until it has thickened but is still pourable, about 10 minutes. Don’t place ganache in the fridge to cool. Test the consistency of the drip by pouring down the side of a glass. If it’s too thick, microwave for 5 to 10 seconds. If it’s too thin, continue to cool.
- Carefully pour some of the ganache over the top of the chilled cake. Use an offset spatula to quickly smooth the ganache over the top of the cake before it sets, spreading evenly just to the cake’s edge. Use a squeeze bottle to gently squeeze one drip at a time down the sides of the cake.
- Before the ganache fully sets, add sprinkles, chocolate curls, or any other decor you like. It won’t adhere properly if you allow the ganache to firm up before adding.
- This cake can be stored, covered with a cake keeper, at a cool, dry room temperature for 2-3 days.*
Recipe Notes
This recipe was originally published in 2014 and recently updated with weight measurements and new photos. Photos by Ashley McLaughlin.
We love the cake! The buttercream is so so so sweet so I ended up making a whipped cream icing with Baileys instead, but absolutely love the base cake recipe. A new staple around here!
How many cupcakes would this make? Thank you.
I made 33
That’s more than I thought. Thanks for the reply!
Can I use plugra butter (unsalted, melted at room temp) in place of the vegetable oil in the cake batter? I also plan on doing the bundt pan version as I am serving this cake at a family function.