
Incredibly rich and moist chocolate cake. The secret ingredient in both the cake and the icing is sour cream!
To make the cake, preheat oven to 350°F. Butter and flour three 8-inch or 9-inch cake pans and line bottoms with parchment paper.
Melt the chocolate and instant espresso (if using) in a bowl placed over a pan of simmering water. Remove from heat and let cool for about 10 minutes.
Place one cake layer on a cake stand or plate and cover the top with half of the filling. Place another layer on top, followed by the rest of the filling.