There are many iterations of chocolate cake, and I love each and every one of them. You could hand me a flourless chocolate cake, a chocolate mug cake, or a no-bake cheesecake, and I’d be thrilled to dig into each and every one of them. There’s one, however, that I don’t get to enjoy very often: Guinness-chocolate cake. I almost never think of making it unless St. Patrick’s Day is around the corner, and I don’t come across it frequently in bakeries or restaurants. The cake is incredibly moist and rich, with a deep chocolate flavor that’s complemented by the beer’s malty, tangy undertones.
The stout-infused chocolate cake recipe below comes from my Birmingham, Alabama-based test kitchen colleague Jasmine Smith. Her sheet cake is balanced, with plenty of flavor from both the chocolate and beer, and a malted vanilla frosting adds just enough sweetness—plus the creamy frosting visually evokes the thick, creamy head on a properly poured stout. Here’s how to make it.
4 Tips for Making a Delicious Guinness-Chocolate Sheet Cake
Use Guinness Extra Stout, if possible. Guinness sells several kinds of beers; their extra stout, which is sold in bottles in the US, has a smooth, creamy finish with toasty coffee notes that complement the chocolate in the cake. Here, we use bottled Guinness Extra Stout, which has less water, more concentrated roasted barley flavor, and residual sugar than the Guinness Draft Stout sold in cans. If you can’t find any Guinness Extra Stout, Dragon Stout or Left Hand Brewery Milk Stout both have a similar flavor profile and would be good substitutes.
Warm up your beer. Some chocolate cake recipes, like devil’s food cake, call for stirring cocoa powder and chocolate into hot water or coffee. Here, we use beer that’s just been brought to a simmer, which helps dissolve the cocoa powder.
Brush the cake with a Guinness syrup. To keep the cake moist, make a simple syrup by whisking Guinness, sugar, and instant espresso powder together in a saucepan over heat on the stovetop, then brush the cake with it. This not only helps the cake stay softer for longer, but also gives the cake additional stout flavor (most of the alcohol will cook off).
Top it with a malted vanilla frosting. Cream cheese helps stabilize the frosting and gives it its rich, creamy texture. Incorporating malted milk powder gives it a delicious nuttiness and savory depth; the ingredient is made from barley that’s been malted—the process of soaking, germinating, and drying grains—which gives it a distinct earthiness. Malted grains are often used to brew beer, and because much of Guinness’ flavor comes from malted barley, the frosting pairs wonderfully with the cake and enhances the bittersweet flavors of the hops and chocolate. If you love malted milk powder as much as I do, then you’ll probably want to eat the frosting all on its own. Just remember to leave some for the cake.
For the Cake: Adjust oven rack to middle position and preheat to 350°F (175°C). Grease a 10- by 15-inch rimmed baking sheet or 9- by 13-inch baking pan with butter and dust with cocoa powder, shaking out excess. (See notes.)
In a small saucepan, bring beer to a simmer over medium heat; remove from heat and set aside. Meanwhile, in a large bowl, whisk flour, sugar, cocoa powder, baking powder, baking soda, and salt together to combine.
Add eggs, milk, oil, and vanilla to flour mixture; whisk until well combined and no streaks remain. Gradually pour warmed beer into batter and whisk to combine. (Batter will be thin.) Pour batter into prepared pan.
Bake until a toothpick or cake tester inserted into the center comes out clean and cake springs back when gently touched, 25 to 30 minutes. Remove from oven and cool completely in pan on a wire rack, about 1 hour.
While the cake cools, prepare the Guinness Syrup: In a small saucepan, whisk beer, sugar, and espresso granules to combine. Bring to a simmer over medium heat; cook, stirring often, until sugar is dissolved, about 2 minutes. Remove from heat.
Using a fork, poke the cooled cake all over. Using a pastry brush, brush cake with syrup until all the liquid is absorbed. (It may look like a lot of liquid, but the cake will soak it all up.)
For the Malted Vanilla Frosting: In the bowl of a stand mixer fitted with the paddle attachment, beat cream cheese, sugar, malted milk powder, vanilla, and salt on medium speed until smooth, using a flexible spatula to scrape down bowl and beater as needed, about 1 minute. Increase the speed to high, then gradually add heavy cream until mixture is smooth and medium-stiff peaks form, 5 to 6 minutes. (Alternatively, frosting can be prepared in a large bowl with an electric hand mixer.)
Using a flexible spatula or offset spatula, spread frosting over cooled cake. Refrigerate until chilled and set, about 1 hour.
Special Equipment
10- by 15-inch rimmed baking sheet, small saucepan, whisk, toothpick or cake tester, pastry brush, stand mixer or electric hand mixer, flexible spatula or offset spatula
Notes
Be sure to use bottled Guinness Extra Stout Beer, which has less water, more concentrated roasted barley flavor, and residual sugar than the Guinness Draft Stout sold in cans. If you can’t find any Guinness Extra Stout, Dragon Stout or Left Hand Brewery Milk Stout both have a similar flavor profile and would be good substitutes.
If using a 9- by 13-inch baking pan, you may have to increase baking time by 3 to 5 minutes.
Dark brown sugar can be substituted for granulated sugar in both the cake and syrup, which will give the dessert deeper caramel notes.
Make-Ahead and Storage
The cake can be baked up to 1 day in advance;once cooled, wrap cake in plastic and store at room temperature. The syrup can be made up to 3 days in advance and refrigerated in an airtight container. The frosting can be made up to 3 days in advance and refrigerated in an airtight container; re-whip in the bowl of a stand mixer fitted with a paddle attachment or in a large bowl using an electric mixer before spreading over cake.
The frosted cake can be loosely covered with plastic wrap and refrigerated for 2 to 3 days.