Rice Krispie Bars 1/4 cup margarine, or butter 32 marshmallows, or 3 cups miniature marshmallows 5 to 6 cups Rice Krispies cereal Melt butter in saucepan. Add marshmallows and cook over low heat, stirring constantly until marshmallows are melted and mixture is well blended. Remove from heat. Add Kellogg's Rice Krispies and stir until well coated. Press mixture into buttered pan. Cut into squares when cool.