1. In large saucepan melt butter over low heat. Add marshmallows and stir until completely melted. Remove from heat. Stir in pudding mix.
2. Add KELLOGG'S RICE KRISPIES cereal. Stir until well coated.
3. Using buttered spatula or wax paper evenly press mixture into 13 x 9 x 2-inch pan coated with cooking spray. Cool. Cut into 2-inch squares.
MICROWAVE DIRECTIONS: In microwave-safe bowl heat butter and marshmallows on HIGH for 3 minutes, stirring after 2 minutes. Stir until smooth. Add pudding mix, stirring until smooth. Follow steps 2 and 3 above. Microwave cooking times may vary.