Coat 3 (8-inch) round cake pans with cooking spray. Line bottoms of pans with wax paper; grease wax paper with shortening, and set aside.
Melt chocolates in a small saucepan over low heat, stirring until smooth.
Beat butter at medium speed with an electric mixer until creamy. Gradually add sugar, beating until light and fluffy. Add eggs, 1 at a time, beating just until yellow disappears after each addition. Stir in melted chocolate and vanilla.
Sift together cake flour and next 3 ingredients; add to butter mixture alternately with buttermilk, beginning and ending with flour mixture. Beat at low speed just until blended. Stir in 1 cup boiling water. Pour batter evenly into prepared pans.
Bake at 350° for 28 to 30 minutes or until a wooden pick inserted in center comes out clean. Cool in pans on wire racks 10 minutes; remove from pans, and cool completely on wire racks.
Place 1 cake layer on a serving plate; spread top with 4 tablespoons Coffee Liqueur Ganache Icing. Spread half of Mocha-Chocolate Cream Filling evenly over ganache on cake layer. Top with second cake layer; spread top with 4 tablespoons Coffee Liqueur Ganache Icing and remaining Mocha-Chocolate Cream Filling. Top with remaining cake layer. Spread remaining Coffee Liqueur Ganache Icing on top and sides of cake. Garnish, if desired.