Remove top 2 inches of sponge cake in one slice. Cut a tunnel thru center of de-capitated cake. Remove the cake bits-by-bits and reserve in small bowl. Set aside.
Dissolve Jell-O gelatin in 1 cup of hot water. Add frozen strawberries (chopped apart for quicker completion of final dessert)-to thoroughly dissolved Jell-O mixture. Add cake pieces to the strawberry Jell-O mixture and stir thoroughly to mix. Once prepared, return by spoonfuls to fill the "tunnel" in cake.
Frost with Cool Whip or own prepared whipped cream topping.