Preheat oven to 300 degrees. Combine crumbs, sugar, and margarine; press firmly on bottom of 9-inch springform pan. In large mixer bowl, beat cheese until fluffy. Gradually beat in sweetened condensed milk until smooth. Add eggs and Real Lemon, mix well. Pour into prepared pan. Bake 50-55 minutes or until center is set; top with sour cream. Bake 5 minutes longer. Cool, Chill. Top with pie filling. Refrigerate leftovers. Taken from Borden advertisement.