Take half of the Eggnog melts and finely chop them. Set aside.
In microwave-safe bowl heat butter and marshmallows on HIGH for 3 minutes, stirring after 2 minutes. Stir until smooth. Microwave cooking times may vary.
Add KELLOGG'S RICE KRISPIES cereal and chopped up Eggnog Melts. Stir until well coated.
Using buttered spatula or wax paper evenly press mixture into 13 x 9 x 2-inch pan coated with cooking spray. Cool. Cut into desired shapes.
Melt remaining Eggnog Melts according to package directions and spoon a thin layer on to the tops of each Rice Krispies Treats. Top with crystal sugar or sprinkles prior chocolate setting up. Enjoy!