MICROWAVE butter in large microwaveable bowl on HIGH 45 sec. or until melted. Add marshmallows; toss to coat. Microwave 1-1/2 min. or until marshmallows are completely melted and mixture is well blended, stirring after 45 sec. Add cereal; mix well.
PAT 1 cup cereal mixture into 3-1/2-inch circle on center of large cutting board sprayed with cooking spray. Add red food coloring and 12 drops yellow food coloring to 2 cups of the remaining cereal mixture; mix well. Tint remaining cereal mixture with remaining yellow coloring.
PAT orange-colored cereal mixture into 1-1/2-inch-wide ring around cereal mixture on cutting board. Repeat with yellow-colored cereal mixture. Cool completely.
CUT cereal mixture into 12 wedges. Insert wooden popstick into rounded end of each wedge.