In small mixing bowl, combine cherries with their syrup and liqueur. Refrigerate overnight. Drain cherries well, reserve liquid. Pat cherries dry between paper towels. Prepare cake according to package directions for two 8-inch cake pans, but DO NOT grease and flour pans. Arrange a parchment circle on bottom of cake pans. Bake according to package directions. Place cake pans in freezer until thoroughly chilled. Invert cakes onto flat cutting board. Invert cakes onto flat cutting board. Level tops of cake. Carefully slice each cake in half horizontally to create four layers. Pour chocolate chips in a small mixing bowl. In a small saucepan, bring cream and butter to a boil. Remove from heat; pour over chocolate chips. Cover bowl with plastic wrap; let stand 3 minutes. Stir mixture until smooth. In mixer bowl, beat mascarpone, cream, sugar and 1/2 cup of reserved cherry liquid until stiff peaks form. Gently arrange one cake layer on serving platter. Using a pastry brush, dab 2 tablespoons of reserved cherry liquid onto cake. Spread 2 tablespoons of chocolate over cake. Spread 1/4 of mascarpone mixture on top of chocolate; top with 1/3 of cherries. Carefully arrange next cake layer over filling; press down lightly to level and set layer below. Repeat layering two more times, ending with mascarpone mixture. Place cake in refrigerator and allow chocolate to set.
The trick to baking a cake that is almost level, and only in need of a small amount of trimming, is using a parchment paper circle on the bottom, and not greasing or flouring the cake pan.