8 inch pastry shell, baked
1/2 c. butter, softened
3/4 c. sugar
2 sq. unsweetened chocolate, melted
1 tsp. vanilla
2 eggs, unbeaten

Cream butter at low speed in mixing bowl. Gradually add sugar, creaming well. Blend in chocolate and vanilla. Add eggs, one at a time, with mixer at medium speed, beating 3-4 minutes after each addition. Spoon into pastry shell. Chill 2 hours. Top with Cool Whip. Serves 6-8.