In keeping with the Irish theme of my Dad’s birthday dinner, I had to make this cake. It is amazingly rich and moist and I want the buttercream on everything that I eat from now on.
Although I could not taste the Guinness in the cake, it really brought out the flavor of the chocolate. I happen to like Bailey’s, so I used a heavy hand for the frosting, but this can be adjusted to taste. The below recipe makes just enough icing to frost the two cakes, so if you would like to add decorative piping, you will want to increase the ingredients.
To make the cake, preheat the oven to 350° F. Grease and flour two 8-inch round cake pans. Line bottom of pan with parchment paper and grease and flour parchment paper.
Combine the stout and butter in a medium saucepan over medium heat. Bring to a simmer. Add the cocoa powder and whisk until smooth. Remove from the heat and allow to cool slightly.
In a large mixing bowl, combine the flour, sugar, baking soda and salt; set aside. In the bowl of an electric mixer fitted with the paddle attachment, beat together the eggs and sour cream to blend. Add the stout-butter mixture and beat just to combine. Mix in the dry ingredients on low speed just until incorporated. Divide the batter evenly between the cake pans. Bake until a toothpick inserted in the center comes out clean, approximately 20 - 25 minutes. Allow to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely. Once the cakes have completely cooled, wrap in plastic and place the cake layers in the freezer for at least an hour. (This is done to make filling and frosting the cakes easier.)
To make the ganache filling, place the chocolate in a heatproof bowl. Heat the cream in a small saucepan until simmering, then pour it over the chocolate. Let sit for one minute and then whisk until smooth. If the chocolate is not completely melted, place the bowl over a double boiler or give it a very short burst in the microwave (15-20 seconds). Add the butter and Bailey’s/whiskey and stir until combined.
Set aside to let the ganache cool until it is thick enough to be spread (you can use the refrigerator to speed the cooling process, but be sure to stir every 10 minutes or so to ensure even cooling). Once the ganache has reached the correct consistency, spread it over the bottom cake layer. Top the ganache with the top cake layer.
To make the frosting, place the butter in the bowl of a stand mixer fitted with the paddle attachment, or use a hand mixer. Beat on medium-high speed until light and fluffy, about 2-3 minutes. Gradually add the powdered sugar until it is all incorporated. Mix in the Bailey’s until smooth. Add more if necessary until the frosting has reached a good consistency for piping or spreading. Frost the cake as desired.
Source: adapted from Annie’s Eats