10 to 12 servings.

1 c. chocolate cookie crumbs
1/4 c. (1/2 stick) melted butter
3 tbsp. sugar
3 (8 oz.) pkg. (1 1/2 lbs.) cream cheese, room temperature
1 c. sour cream
1 c. sugar
2 tbsp. flour
3 eggs, separated
2 tbsp. creme de cacao
1 (6 oz.) pkg. semisweet chocolate chips, melted
1 c. whipping cream

Combine cookie crumbs, butter and sugar. Press evenly on bottom of 9 inch springform pan. Chill while preparing the filling.

Preheat oven to 350 degrees. Beat cream cheese, sour cream, sugar and flour thoroughly. Add egg yolks, one at a time, blending well after each addition. Whip egg whites until almost stiff but not dry and gently fold into cheese mixture. fold in liqueur.

Gently swirl slightly cooled chocolate through cheese mixture to give a marbled effect. Transfer carefully to springform pan and bake 60 minutes. Turn off oven and let cake cool with door open. When cool remove sides of springform.

Whip cream. Using a pastry tube, pipe a frill around base of cake. Refrigerate until serving time.