CRUST:

1 c. chocolate wafer/cookie crumbs
1/4 c. melted butter
3 tbsp. sugar

Combine crumbs, butter and sugar. Press evenly in the bottom of a 9" spring form pan. Chill while preparing filling.

FILLING:

3 (8 oz.) pkgs. cream cheese
1 c. sour cream
1 c. sugar
2 tbsp. flour
3 eggs, separated
2 tbsp. creme de cacao
1 (6 oz.) pkg. chocolate chips, melted

Beat cream cheese, sour cream, sugar and flour. Add egg yolks, one at a time, blending after each addition. Whip egg whites until almost stiff 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 pan. (Or, you may pour cream cheese mixture in the pan first, then pour chocolate in and swirl chocolate around.) Bake in preheated 350 degree oven for 60 minutes.

Turn oven off and let cheesecake cool in oven with door open. When cool, remove sides of springform pan.

One cup whipping cream can be piped on the top of the cheesecake, if desired.

Refrigerate until served. The flavor of this cake is better if made one day prior to being served. Serves 10 to 12.