1 1/4 C. chocolate wafer crumbs or graham cracker crumbs (about 20 wafers or 16 squares)
1 C. plus 2 T. sugar
3 T. butter, melted
1 (6 oz.) package semisweet chocolate chips
2 (8 oz.) packages cream cheese, softened
2 t. vanilla
1 C. dairy sour cream
Sour Cream Topping
Mix wafer crumbs, 2 tablespoons sugar and margarine. Press in bottom of a 9×3-inch springform pan.
Heat chocolate chips over low heat, stirring occasionally, until melted; cool slightly. Beat cream cheese and vanilla in 2 1/2-quart bowl until smooth. Add remaining 1 cup sugar gradually, beating until fluffy. Beat in eggs, one at a time. Beat in chocolate and sour cream until smooth. Pour into pan.
Bake in preheated 300°F. oven 65 to 70 minutes or until center is firm. Cool to room temperature. Refrigerate at least 3 hours. Loosen edge of cheesecake with knife before removing side of pan.
Spread with Sour Cream Topping. Sprinkle with chopped or grated chocolate, if desired. Refrigerate any remaining cheesecake.
Sour Cream Topping: Mix 1 C. sour cream, 2 T. sugar and 2 t. vanilla.
Makes 12 servings.