Step 4: Assemble the Layers, Frost and Freeze
Spread the filling on the top of one of the cake. Place the second cake on top of the first. If they cakes are not level, level with a knife or a cake leveler. Frost the top cake. Smooth the frosting with wax paper. Place the cakes in the freezer with the wax paper in place. Freeze overnight, or until the cake is completely frozen.