Crust:
1-1/2 – 2 cups graham cracker crumbs
½ cup margarine, melted

Filling:

3 (8 ounce) packages tofutti cream cheese
1-1/2 cups sguar
1 cup tofutti sour cream
1-1/2 teaspoons vanilla
4 eggs
¾ cup semisweet chocolate chips, divided

Preheat oven to 350 degrees. For crust, combine graham cracker crumbs and melted margarine. Press into the bottom of a 10-inch springform pan. Refrigerate while you make the filling.
Place tofutti cream cheese in a large mixing bowl. Beat at low speed, gradually adding the sugar. Beat in the sour cream and vanilla. Beat in the eggs, one at a time. Stir in ½ cup chocolate chips and pour into crust. Sprinkle with remaining chocolate chips. Bake for 45 to 50 minutes, or until top has set.