2 cups stout beer (such as Guinness)
2 cups (4 sticks) unsalted butter
1 1/2 cups unsweetened cocoa powder (preferably Dutch-process)
4 cups all purpose flour
4 cups sugar
1 tablespoon baking soda
1 1/2 teaspoons salt
4 large eggs
1 1/3 cups sour cream
¾ lb cream cheese (leave on the counter overnight)
½ lb unsalted butter (leave on the counter overnight)
1 tsp Bailey’s Irish Cream (or to taste)
1 lb powdered sugar, sifted
1 ¼ cups semisweet chocolate chips
¾ tbsp light corn syrup
¾ cup heavy cream
† Photographs were taken while I was making 3 cakes, hence the massive quantities.
Bring 2 cups stout and 2 cups butter to simmer in heavy large saucepan over medium heat. Add cocoa powder and whisk until mixture is smooth. The mixture will thicken and resemble brownie mix. Cool slightly.
Whisk flour, sugar, baking soda, and 1 1/2 teaspoons salt in large bowl to blend. Using electric mixer, beat eggs and sour cream in another large bowl to blend. Add stout-chocolate mixture to egg mixture and beat just to combine. Add flour mixture and beat briefly on slow speed.
Using rubber spatula, fold batter until completely combined
among prepared pans. Bake cakes until a toothpick inserted into center of cakes comes out clean, about 35-45 minutes.
Transfer cakes to rack; cool 10 minutes. Turn cakes out onto rack and cool completely (2-3 hours).
Mix the cream cheese, butter and Bailey’s in the bowl of an electric mixer fitted with the paddle attachment until just combined. Add the sifted sugar and mix until smooth.
Place 1 cake layer on plate, upside down. Spread icing over, with about a quarter inch bare edge. Top with second cake layer, upside down. Repeat icing technique. Top with third cake layer, right-side up. Finish frosting the cake.
For the ganache:
In a heatproof bowl, place the chocolate chips and the corn syrup. Bring the heavy cream to a full boil. Pour the cream over the chocolate and whisk it until shiny and smooth then set it aside.
Pour ganache over the top of the cake and, with a cake spatula, smooth the top of the cake and allow ganache to spill over the sides. Because of how good this is, sloppy is OK. Refrigerate for 20 minutes or longer.
Serve the cake cold or allow it to come to room temperature before serving.