Frozen Lemon Squares
["1/4 c. margarine, melted", "1 1/4 c. graham cracker crumbs", "1/4 c. sugar", "3 egg yolks", "1 (14 oz.) can condensed milk", "1/2 c. lemon juice", "whipped cream or topping"]
["Combine margarine, crumbs and sugar; press onto 8-inch square pan.", "In bowl beat egg yolks.", "Stir in condensed milk and lemon juice.", "Add yellow food coloring if desired.", "Pour into crust. Top with whipped cream or topping and freeze.", "Keep cool."]
["margarine", "graham cracker crumbs", "sugar", "egg yolks", "condensed milk", "lemon juice", "whipped cream"]