- 3 cups all-purpose flour
- 1 & 1/2 teaspoons baking soda
- 3/4 teaspoon salt
- 1 & 1/2 cups unsalted butter, softened
- 1 & 1/2 cups granulated sugar
- 1 & 1/2 cups firmly packed light brown sugar
- 6 large eggs, at room temperature
- 9 ounces unsweetened chocolate, melted
- 1 & 1/8 cups buttermilk
- 1 & 1/2 teaspoons vanilla extract
- 3/8 cup sour cream
- 1/3 cup unsalted butter, softened
- 3 ounces cream cheese, softened
- 3 & 3/4 cups sifted confectioners’ sugar
- 3 tablespoons heavy cream
- 1/2 teaspoon vanilla extract
- 1/8 teaspoon salt
- 2 tablespoons Frangelico
- 2/3 cup unsalted butter, softened
- 16 ounces cream cheese, softened
- 1/2 cup Dutch-process cocoa powder
- 3 cups sifted confectioners’ sugar
- 2 tablespoons sour cream
- 1 teaspoon vanilla extract
To make the cake:
Preheat oven to 350°. Grease and lightly flour three 9-inch square baking pans. Line the bottoms with parchment paper.
Sift together flour, baking soda, and salt. Set aside.
Using an electric mixer on medium speed, mix butter and sugars until fluffy. Add eggs one at a time, beating well after each. Add chocolate, and mix until well incorporated. Add dry ingredients in three parts, alternating with buttermilk and vanilla. Beat until smooth. Stir in sour cream.
Divide batter equally and pour into prepared pans. Bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean. Cool in pans for 10 minutes. Then, remove from pans and cool completely on wire racks.
To make the cream cheese frosting:
Mix butter and cream cheese with a wooden spoon until blended. Add 2 cups of sugar, half of the heavy cream, and salt. Beat until smooth. Add remaining sugar, cream, vanilla, and Frangelico. Mix until smooth, but do not overmix. If frosting is too thick, add a few drops of heavy cream.
Spread frosting between cake layers. If necessary, place frosting in refrigerator before spreading onto cake layers.
To make the chocolate cream cheese frosting:
Mix butter and cream cheese until smooth. Stir in cocoa powder. Add sugar in three portions, alternating with sour cream. Beat until smooth and creamy. Stir in vanilla extract.
Spread frosting on top and sides of cake. If necessary, place frosting in refrigerator before spreading on cake.
Place frosted cake in refrigerator to allow it to set.