Grease rectangular pan, 13 x 9 x 2"
Heat syrup, margarine and morsels to boiling, stirring constantly. Remove from heat, stir in vanilla.
Pour over cereal in bowl; toss until coated. Fold in marshmallows, 1 cup at a time. *Add yogurt chips here if desired* Press in pan with buttered back of spoon. Let stand 1 hour.
Cut into 2" squares. Store loosely covered at room temperature up to 2 days. Makes 24 squares.