Melt butter in large sauce pan on low-medium heat until melted.
Add mini marshmallows; stir until mostly melted. Add in green food coloring; stir until completely melted and green food coloring is mixed in. Remove from heat.
Add KELLOGG'S Rice Krispies cereals. Stir until well coated.
Using a spatula, press mixture into a 13x9″ pan coated with cooking spray.
Gently press heart quin onto Rice Krispies Treats; add throughout pan so that each square you cut will have a heart quin.
Let treats stand until set. Cut into delicious squares. Eat & Enjoy!
Notes
Grinch Rice Krispies Treats should be stored in an airtight container and will keep for 4+ days.