1 lg. sponge cake
6 lg. butterfingers
1 lg. Cool Whip
2 c. powdered sugar
4 egg yolks
1 1/2 sticks butter

Break sponge cake into small pieces. Place in bottom of pan. Melt butter, sugar and egg yolks together over low heat until thin enough to pour over cake. Pour and let cool. Crush candy bars until crumbly (set aside 1/4 cup of candy to top cake). Sprinkle over egg mixture. Top this layer with Cool Whip and sprinkle the rest of candy over this chill overnight.