Spray a 9X13 pan with a non-stick cooking spray and set aside.

Place the butter and marshmallow in a sauce pan and melt over low heat stirring frequently.

Once the ingredients are melted and combined, remove from heat and gradually stir in the Rice Krispie Cereal.  Mix until the cereal is coated in the marshmallow and butter mixture.

Then gently fold in the M&Ms and sprinkles (reserve some for topping).

Press the mixture into the 9X13 pan.  I spray a piece of parchment paper with non-stick spray and use that parchment paper to press the cereal down into the baking dish.

Then top with the reserved M&Ms and sprinkles.  Gently press these down so that they stick into the Rice Krispie treats.

Let the Rice Krispie treats sit at room temperature for 1 hour and then they are ready to slice, serve and enjoy!