Chocolate Lover's get ready. This is the ultimate indulgence. Two layers of rich, buttery chocolate stout cake topped with creamy frosting.
Preheat your oven to 350 degrees Fahrenheit. Adjust the oven rack to center position. Generously butter two 9-inch round cake pans and line with parchment paper. Butter the paper, too.
In a heavy saucepan, slowly melt the butter with the stout beer. Bring to a simmer, stirring frequently until all of the butter has melted and the mixture is steamy. Whisk in the cocoa powder until smooth. Remove from heat and let cool for several minutes.
Next, stir together the flour, sugar, baking soda, and salt in a large bowl.
In a separate large bowl, beat the eggs, sour cream, and vanilla with a handheld mixer until smooth, about 2 minutes.
Slowly pour the butter-beer-chocolate mixture into the egg mixture, beating on low speed until just combined.
Then, add the flour mixture to the cake batter a cup at a time, STIRRING (not beating) by hand until the dry ingredients are just incorporated. Do not over mix.
Pour the chocolate cake batter evenly into the prepared cake pans. Bake in the pre-heated oven for 35 - 40 minutes until a pick inserted in the center of the cake comes clean.
Remove the cake from the oven and let cool in the pan on a wire cooling rack for 15 minutes. Gently loosen the cake from the pan by running a flat butter knife around the edges.
Next, carefully turn the chocolate cake layers out onto the cooling rack. Cool completely.
Heat two cups of heavy cream in a heavy sauce pan over medium-low heat until hot. Remove from heat and stir in semisweet chocolate pieces until melted and smooth.
Place the frosting in the fridge. Stir every 15 - 30 minutes until it is cooled and spreadable (about 2 hours).
Frost the cake by spreading about 3/4 cup of the frosting on the bottom layer. Top with the top layer and frost the top and sides.
Optional: sprinkle the top with flakes of sea salt.