Freeze the cake for at least 2 hours or overnight.
Split cake horizontally into three layers. Place bottom layer on a freezer-safe serving plate; top with about 1 cup sherbet. Repeat layers. Top with remaining cake layer. Fill center with remaining sherbet. Frost top and sides with whipped topping. Gently spread preserves over top of cake.
Loosely cover and store in freezer. Thaw in the refrigerator for 30 minutes before slicing with a serrated knife. Garnish with raspberries if desired.