1. In large saucepan melt butter over low heat. Add marshmallows and stir until completely melted. Remove from heat.
2. Add Kellogg's® Rice Krispies® cereal. Stir until well coated.
3. Using buttered spatula or wax paper, evenly press mixture into 15 x 10 x 1-inch pan coated with cooking spray. Cool. Using cookie cutters coated with cooking spray cut twelve 2 1/2-inch circles and twelve 1 1/2-inch circles. Frost the tops of the 1 1/2-inch circles.
4. For each reindeer use frosting to attach one 1 1/2-inch circle, frosting side up, to each 2 1/2-inch circle. Use scraps of the cereal mixture to shape into twenty-four ears. Use frosting to attach ears to each reindeer. Break pretzel twists into pieces. Push two pretzel pieces into each for antlers. Decorate with frosting and gum drops. Best if served the same day.
In microwave-safe bowl heat butter and marshmallows on HIGH for 3 minutes, stirring after 2 minutes. Stir until smooth. Follow steps 2 through 4 above. Microwave cooking times may vary.