In medium bowl, combine crumbs, 1/4 cup of the sugar and the melted margarine. Press mixture firmly on bottom and side of 9-inch pie plate (not springform); set aside.
In small saucepan, over low heat, melt 3 squares of the chocolate; set aside. In medium bowl, with electric mixer at medium speed, beat cream cheese and remaining 1/2 cup sugar until creamy. Beat in 1/2 cup sour cream and eggs until smooth. Blend in melted chocolate and vanilla. Pour into prepared crust. Bake at 325 degrees F for 35-40 minutes or until cheesecake is slightly puffed and center is set. Remove cheesecake from
oven (leave oven turned on).
Blend remaining 1 cup sour cream and brown sugar; spread over cheesecake. Return cheesecake to oven. Bake for 5 minutes more. Cool to room temperature. Melt remaining 1 ounce chocolate and drizzle over cheesecake. Chill at least 4 hours. Makes 8 servings.
*Note From Diana's Desserts:
Lynne, who submitted this recipe doesn't think that Oreo Cookie Crumbs are still being made. So, of course you can crush your own Oreo cookies for the crust, or buy a ready-made Oreo Cookie Crust.
Source: Oreo Cookie Crumbs Box
Submitted By: Lynne Parrish
Date: September 22, 2002