Crust:

� 1 cup all-purpose flour
� 1/4 cup diet margarine
� 3 tablespoons cold water

Custard:

� 3 Egg yolks
� 1 tablespoon cornstarch
� 1 envelope unflavored gelatin
� 3/4 cup lemon juice
� 3/4 cup boiling water
� 1 tablespoon grated lemon rind
� 1 tablespoon diet margarine
� sugar substitute equivalent to 1/2 cup sugar

Topping:

� 2 egg whites
� 1 packet low-calorie whipped topping � 1/2 cup skim milk
� 1 lemon; thinly sliced

Preparation:

Crust: In food processor , combine flour and margarine; process with on-off motion till coarse crumbs. Add water and blend until mixture forms a ball. Roll out on a floured surface to 12 inch circle, line 9 inch pie plate. Trim edges. Cover pastry with 9 inch circle of waxed paper; prick holes through paper and pastry with fork. Weigh down with dried beans or rice; bake in 350F oven 10 minutes. Remove beans and paper; bake 15 to 20 minutes or until lightly browned. Let cool.

Custard: In food processor or blender, blend egg yolks, cornstarch, gelatin and lemon juice; add boiling water and blend thoroughly. Blend in lemon rind and margarine. Pour in small pan and heat to boiling, stirring constantly, until thickened. Let cool; slightly; stir in sweetener. Pour in pie crust. Chill for 2 hours.

Topping: In bowl, beat egg whites until stiff, but not dry, peaks forms. Prepare whipped topping according to package directions, substituting milk for water. Gently fold in egg whites. Spread over chilled custard. Garnish with lemon slices. Serve immediately.