Preheat oven to 325°F. Grease and flour pan. Dissolve gelatin in boiling water. Stir in cold water; set aside at room temperature. Prepare and bake cake 45-50 minutes. Cool cake in pan on rack for 10 minutes. Level cake with large sharp knife. Turn cake onto platter or foil covered cake board; cool an additional 10-15 minutes. Poke deep holes through top of cake with meat fork; space holes about 1 inch apart. With cup, slowly pour gelatin mixture over cooled cake. Set in refrigerator while preparing filling. For filling, mix instant pudding mix and cold milk in bowl; fold in whipped topping. Using a long serrated knife, split cake into two horizontal layers. A cookie sheet makes a convenient large "spatula" for lifting and replacing the top layer. Spread filling on bottom layer, add banana slices and replace top layer. Ice cake with white buttercream icing.

Makes approximately 45-50 servings.