A high altitude chocolate Guinness cake with Baileys frosting for St. Patrick’s Day! This is a very moist chocolate cake made with Guinness draught stout beer and black cocoa powder, frosted with Baileys Irish cream buttercream.
You might also love this chocolate Kahlua and cream cake, easy Irish soda bread, and poppy seed Irish tea cake.
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Why You’ll Love This Recipe
Rich Chocolatey Flavor. If you’re worried that this chocolate Guinness cake will taste strongly of beer, don’t be. I’m not a beer drinker myself – in fact, I hate the stuff. But I loved this cake. Guinness is known for having a very smooth, creamy, dark, velvety flavor, which perfectly complements and deepens the flavor of the cocoa powder, and pairs so well with the Irish cream buttercream.
Perfect for St. Patrick’s Day. Whether you’re Irish or not, you can still wear something green and celebrate St. Patrick’s Day with a delicious cake that everyone will love.
Smaller Size. Today’s recipe makes a modestly sized two layer 6 inch cake that serves 8 people. See the recipe variations section below for making a larger cake.
High Altitude Tested. I develop all the recipes on my site for Denver’s altitude of 5,280 feet. If you’re at a lower or higher elevation, please see my FAQs for guidance on adjusting recipes for your altitude.
See the recipe card at the end of the post for the full ingredients list and instructions.
Ingredients
Cake
- Guinness. You’ll need one can or bottle (between 12-14 ounces) of Guinness stout. To get the most flavor from the Guinness without watering the cake down, you’ll be reducing the Guinness on the stove first, before adding it to the cake batter. The concentrated Guinness will not only add more flavor to the cake, but the boiling liquid will help to “bloom” the cocoa powder for a richer chocolate taste.
- Flour. All purpose flour gives the cake structure and strength.
- Sugar. Granulated sugar adds sweetness and moisture.
- Cocoa Powder. You’ll need two kinds of unsweetened cocoa powder for this chocolate Guinness cake. Dutch processed cocoa powder will give the cake a smooth, rich chocolate flavor, while black cocoa powder will intensify the chocolate and give the cake its luscious black color, similar to the color of a glass of Guinness topped with a frothy layer of foam.
- Baking Soda + Baking Powder. Leavening agents.
- Salt. Balances the sweetness and enhances flavors.
- Vegetable Oil + Sour Cream. Keeps the cake moist, while the acidity in the sour cream adds tenderness.
- Vanilla Extract. Flavor.
- Eggs. Gives the cake moisture and strength.
Buttercream
- Butter. Use unsalted butter, or if you use salted butter, then omit the extra salt in the recipe.
- Powdered Sugar. Sweetens and thickens the frosting.
- Meringue Powder. Adds stability and improves the texture.
- Salt. Balances the sweetness.
- Irish Cream Liqueur. You can use Baileys or any other brand of Irish cream liqueur to add a rich and creamy flavor and texture to the frosting.
Instructions
Cake
- Pour the Guinness into a small saucepan. Bring to a boil, then steadily simmer the Guinness over medium heat until it’s reduced to 3/4 cup. This may take 20-30 minutes, depending on how fast the Guinness is boiling.
- Preheat the oven to 350 F, and position a rack in the center of the oven. Lightly spray the bottoms of two 6-inch cake pans with non-stick baking spray.
- In a bowl, sift together the flour, sugar, cocoa powders, baking soda, baking powder and salt.
- Separately, whisk together the oil, sour cream, vanilla and eggs. Add the wet ingredients to the dry ingredients, and pour in the hot Guinness. Whisk just until smooth.
- Divide the batter between the pans, and bake for about 28-30 minutes, until the tops spring back when gently touched, and a toothpick or cake tester inserted into the cake comes out clean.
- Set the pans on a cooling rack and cool the cakes completely before frosting.
Buttercream
- In the bowl of your stand mixer fitted with the paddle attachment, beat the butter for one minute until smooth. With the mixer on low, add the powdered sugar by spoonfuls, the meringue powder and salt, mixing until combined. Add the Baileys.
- Increase the speed to medium and whip the buttercream for 4-5 minutes, scraping the bowl down several times, until very light and fluffy. Turn the speed down to “stir” and mix for 1 more minute.
- If the cakes have a domed top, use a sharp, non-serrated knife to slice off a small portion of cake to level the cake layers.
- For the naked cake pictured, place one of the layers of cake on a serving plate or cake pedestal, and frost with a thick layer of buttercream. Repeat with the second layer of cake, then lightly scrape the buttercream around the sides to leave the sides of the cake mostly bare. You’ll likely have some buttercream leftover, so if you double the cake recipe for a larger cake, you don’t need to double the buttercream, too.
- If frosting the cake all over, layer the cakes with a thinner layer of buttercream in between, frost the cake all over with a thin crumb coat of buttercream, chill the cake for 30 minutes, then frost the cake with a final smooth coat of buttercream.
Recipe Variations
Whipped Cream. Instead of buttercream, see this Chocolate Kahlua and Cream Cake for my recipe for mascarpone whipped cream frosting. You can add several tablespoons of Baileys to the whipped cream frosting as well.
One Layer 8-inch Cake. To make a one layer 8-inch cake instead of a two layer 6-inch cake, pour the batter into a round or square 8-inch cake pan and bake for about 35 minutes.
Two Layer 8-inch Cake. For a larger 8 inch cake that serves 16 people, divide the cake batter between two or three 8 inch round cake pans. Bake for about 25-35 minutes, testing the cakes for doneness. There’s no need to double the buttercream.
Sheet Cake. For a sheet cake, bake the batter in a 9×13 inch baking pan for about 38-42 minutes. There’s no need to double the buttercream.
Be sure to read all of my BAKING FAQs where I discuss ingredients, substitutions and common questions with cake making, so that you can be successful in your own baking! I also suggest reading these comprehensive posts on making Perfect American Buttercream, How to Stack, Fill, Crumb Coat and Frost Layer Cakes and How to Use Piping Bags.
Frequently Asked Questions
Chocolate Guinness cake does not have a strong beer flavor, so even non-beer drinkers will enjoy this cake with its rich, dark, velvety chocolate flavor.
Store leftover cake in an airtight container at room temperature for up to 3 days.
Yes, you can freeze the assembled and frosted cake in an airtight container for up to 2 weeks. Unfrosted cake layers can be wrapped in several layers of plastic wrap and frozen for up to 3-6 months.
I used Cacao Barry Extra Brute Dutch processed cocoa powder and The Cocoa Trader Black Cocoa Powder.
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High Altitude Chocolate Guinness Cake
All recipes on Curly Girl Kitchen are developed for high altitude at 5,280 feet. See FAQs for adjusting to higher or lower elevations.
Equipment
- 6-inch Round Cake Pans (x2)
- Stand Mixer with Paddle Attachment
Ingredients
Cake
- 1 can or bottle Guinness (12-14 oz)
- 1 cup all-purpose flour, fluffed, spooned and leveled
- ¾ cup + 2 tbsp granulated sugar
- ¼ cup unsweetened Dutch processed cocoa powder
- 2 tbsp black cocoa powder
- ½ tsp baking soda
- ¼ tsp baking powder
- ½ tsp coarse Kosher salt (if using table salt, use half the amount)
- ½ cup vegetable oil
- ¼ cup sour cream
- 1 ½ tsp vanilla extract
- 2 large eggs
Buttercream
- 1 ½ cups unsalted butter, softened to room temperature
- 3 cups powdered sugar
- 2 tsp meringue powder, optional
- ¼ tsp coarse Kosher salt (if using table salt, use half the amount)
- 3 tbsp Baileys Irish cream liqueur
Instructions
Cake
- Pour the Guinness into a small saucepan. Bring to a boil, then steadily simmer the Guinness over medium heat until it's reduced to 3/4 cup. This may take 20-30 minutes, depending on how fast the Guinness is boiling.
- Preheat the oven to 350 F, and position a rack in the center of the oven. Lightly spray the bottoms of two 6-inch cake pans with non-stick baking spray.
- In a bowl, sift together the flour, sugar, cocoa powders, baking soda, baking powder and salt.
- Separately, whisk together the oil, sour cream, vanilla and eggs. Add the wet ingredients to the dry ingredients, and pour in the hot Guinness. Whisk just until smooth.
- Divide the batter between the pans, and bake for about 28-30 minutes, until the tops spring back when gently touched, and a toothpick or cake tester inserted into the cake comes out clean.
- Set the pans on a cooling rack and cool the cakes completely before frosting.
Buttercream
- In the bowl of your stand mixer fitted with the paddle attachment, beat the butter for one minute until smooth. With the mixer on low, add the powdered sugar by spoonfuls, the meringue powder and salt, mixing until combined. Add the Baileys.
- Increase the speed to medium and whip the buttercream for 4-5 minutes, scraping the bowl down several times, until very light and fluffy. Turn the speed down to "stir" and mix for 1 more minute.
- If the cakes have a domed top, use a sharp, non-serrated knife to slice off a small portion of cake to level the cake layers.
- For the naked cake pictured, place one of the layers of cake on a serving plate or cake pedestal, and frost with a thick layer of buttercream. Repeat with the second layer of cake, then lightly scrape the buttercream around the sides to leave the sides of the cake mostly bare. You'll likely have some buttercream leftover, so if you double the cake recipe for a larger cake, you don't need to double the buttercream, too.
- If frosting the cake all over, layer the cakes with a thinner layer of buttercream in between, frost the cake all over with a thin crumb coat of buttercream, chill the cake for 30 minutes, then frost the cake with a final smooth coat of buttercream.
I used this recipe at 9000 ft with just a very slight reduction of baking powder. It was a hit out of the park with our group!
I made it as cupcakes so everyone could get a sample. It made about 15.
Chocolate Guinness cake is a keeper!
I’m so glad everyone loved it!
Doubled the recipe for three 8”. Came out great!
This recipe deserves a 10 star review! I made it for St. Patrick’s Day and my partner and I loved it. The cake texture is perfect, light and moist. The frosting balances with the cake well, and the flavors are delicious and not overly sweet. It was my first attempt at a layered cake (I normally do single layer or sheet cakes) and I’ll definitely be trying more cake recipes from this site.