Break up pound cake into small pieces. Crush butterfingers.
In medium bowl, mix together 2 cups conf. sugar, 1 stick melted butter, and egg yolks till smooth. Fold in thawed whipped topping.
In 3L casserole, layer 1/2 pound cake, 1/2 whipped topping mixture, and 1/2 crushed butterfingers. Do last 1/2 pound cake, Whipped topping mix, and top with Butterfingers. Cover and refridgerate a few hours before serving.