1. Make any Feingold approved cake and pour the batter into a greased 9x13-inch baking pan and bake at 350 degrees until done. When the cake is done, let it cool to room temperature.
2. When the cake has cooled, slice it in half and place each half on a wax-paper or parchment covered cookie sheet, or a platter or tray that will fit into your freezer.
3. Using FG approved Ice Cream, slice the ice cream through the middle so that you have two 2-inch thick sheets of ice cream. Lay a half upon each of the cakes. Slice the edges of the cake all the way around so that the cake is the same size as the ice cream on top. Work quickly so that the ice cream doesn't melt. When both cakes have been trimmed, place them into the freezer for an hour or two.
4. When you are ready to frost the cake, take 4 cups of vanilla ice cream (or 2 pints) out of the freezer for about 20-30 minutes to soften. Stir the ice cream so that it is smooth, like frosting. Use a frosting knife or spatula to coat each cake with the ice cream. Cover the entire surface thoroughly so that you cannot see any of the cake. Pop the cakes into the freezer for an hour or so to set up.
5. When the cakes have set, fill a pastry bag (with a fancy tip) with approved frosting to decorate all around the top edge of the cake, the bottom edge of the cake. Cover the cakes and keep them in the freezer until you are ready to serve them.
6. When you are ready to serve the cakes, leave them out for 10-15 minutes before slicing. Cut the cakes with a sharp knife that has been held under hot water.
Makes 2 cakes (approx. 10 servings each)