2 COMBINE graham cracker crumbs and margarine in small bowl. Press onto bottom of 9-inch springform pan.
3 BEAT cream cheese, ricotta cheese and sugar until creamy. Add pumpkin, orange juice, evaporated milk, vanilla extract, pumpkin pie spice and orange peel; beat until well blended. Add egg substitute and beat just until blended. Pour into crust.
4 BAKE for 60 to 65 minutes or until edges are set but center still moves slightly. Cool in pan to room temperature on wire rack; spread with Topping. Refrigerate for several hours or overnight. Remove side of springform pan.
5 COMBINE 1/2 cup light sour cream, 1 tablespoon granulated sugar and 1 teaspoon orange juice in small bowl.