I’ve been wanting to make this cake for quite a while, but I needed an occasion and more people to help me eat it. My Grandpa’s birthday was last weekend, so I volunteered to bring the dessert and made this. The cake is dense and moist, the filling is very, very rich, and the icing is a little lighter and very sweet. I spread the filling pretty thick, but I think next time I’ll make it thinner. I also might make an extra half of the batter and make three layers of cake with thin layers of filling in between. 1/2 cup of butter for the icing barely covered the cake for me in a thin layer, so if you like it thick, or just want to be on the safe side, you can use 3/4 or 1 cup of butter and adjust sugar accordingly.
Adapted from Smitten Kitchen
1 cup Guinness (or other stout)
1 cup (2 sticks) unsalted butter
3/4 cup unsweetened cocoa powder
2 cups all purpose flour
1 1/2 cups white sugar
1/2 cup brown sugar
1 1/2 teaspoons baking soda
3/4 teaspoon salt
2 large eggs
2/3 cup sour cream
8 ounces bittersweet chocolate
2 ounces semi-sweet chocolate
1 cup heavy cream
3 tablespoons butter, room temperature
2 to 3 teaspoons Jameson (or other Irish whiskey)
2 to 4 cups confections sugar
1/2 to 1 cup unsalted butter, at room temperatue
3 to 4 tablespoons Bailey’s (or milk or heavy cream)
1 ounce semi-sweet chocolate, shaved or grated
Preheat oven to 350F. In a small saucepan, heat Guinness and butter to a simmer, then add cocoa powder and whisk until combined. Cool slightly (until it’s not too hot to touch). In a separate bowl, combine flour, sugars, baking soda and salt. In another large bowl, beat eggs and sour cream together with a hand mixer until blended. Add Guinness mixture and beat again until just blended. Add flour mixture and beat on low briefly, then fold with a spatula until fully combined. Divide evenly into two 9×9 square or 9″ round pans and bake for 20-24 minutes, or until toothpick inserted in center comes out clean. Let cool for a few minutes, then turn out onto cooling racks.
Chop chocolate into small squares and place in medium heatproof bowl. Heat cream until simmering, then pour on top of chocolate. Let sit for one minute and then stir until smooth. If the chocolate is not quite melted, microwave in increments of 20 seconds and stir until smooth. Mix in butter and Jameson’s. Let set until spreadable. Too speed the cooling process, you can place it in the refrigerator, but be sure to check and stir it frequenly so it doesn’t stiffen too much before spreading it.
Place bottom layer of cake upright on whatever dish you’ll be serving it on. With a spatula, spread filling onto cake to whatever thickness you prefer (it’s very rich), then place second layer upright on top. If you have noticeable low or high spots in your layers, try to turn the cake layers so a thick spot is on top of a thin one or vice versa. You can also use the filling to try to even it out so you end up having a uniform top to the cake. Once you place the second layer on, you can fill in any gaps on the edges with more filling. After getting the second layer on, allow the filling to set completely before trying to frost, so it doesn’t blend into the icing.
Whip the butter with a hand mixer until very fluffy. Add the powdered sugar a few tablespoons at a time. When the frosting appears thick enough to spread, add the Bailey’s. For a topping, I used a vegetable peeler to shave little curls of chocolate off a chocolate bar and then sprinkled them over the top.