4 tbsp. butter, melted
1 1/4 c. chocolate cookies, crushed
6 tbsp. Grand Marnier liqueur, divided
2 (8 oz.) pkgs. cream cheese, room temperature
1 c. sugar
3 eggs
6 oz. semi-sweet chocolate, melted
1 c. sour cream
Zest of 1/2 orange, grated or minced

CRUST: Heat oven to 350 degrees. Lightly grease sides of 10" springform pan. Pour melted butter into pan, stir in crushed cookies, press onto bottom only. Bake 10 minutes, sprinkle with 2 tablespoons liqueur; set aside.

BATTER: Mix cream cheese, sugar, eggs and zest in large bowl, or in food processor with knife blade until smooth. Add melted chocolate, blend thoroughly. In separate bowl, mix sour cream with remaining 4 tablespoons liqueur, blend into cream cheese mixture.

Bake 40 minutes or until cheesecake jiggles slightly in middle only. Remove from oven, cool thoroughly on wire rack before removing side of springform pan. Refrigerate overnight.

OPTIONAL GARNISHES: Top with very thin slices of additional orange zest. Serve with a dollop of whipped cream, flavored with 2 tablespoons Grand Marnier liqueur