Crust:

18 Oreo Chocolate sandwich cookies, finely crushed
2 tbsp. butter, melted

Mix crumbs and butter; press onto bottom of 9-inch spring form pan.

Bake at 325°F for 10 minutes.

Filling:

4 pkg. (8-oz. each) cream cheese, softened
1 c. sugar
1 tsp. vanilla
1 pkg. (18 squares) semisweet baking chocolate, melted, slightly cooled
1/4 c. hazelnut liqueur (optional)
4 eggs

Beat cream cheese, sugar, and vanilla with electric mixer until well blended. Add chocolate, liqueur, and eggs. Mix just until blended. Pour over crust.

Bake at 325°F for 55 to 60 minutes or until center is almost set if using a silver spring form pan or bake at 300°F for 60 to 65 minutes if using a dark nonstick spring form pan. Run a knife around the rim to loosen cake; cool before removing rim of pan. Refrigerate 4 hours or overnight.

Makes 12 servings.