For the Rice Krispies treats:

1. Spray your 9″ x 13″ baking pan with cooking spray.
2. Get a large pot and melt your butter on low heat until completely melted.
3. Add in the marshmallows and continuously mix until they are completely melted and combined with the butter.
4. Remove the pot from the heat and add the vanilla extract and the Rice Krispies cereal. Stir to combine.
5. Spray a silicone spatula with cooking spray and use to pour the mixture into your greased baking pan. Continue using the spatula to gently press down and evenly distribute the Rice Krispies all throughout the pan.
6. Allow the Rice Krispies to cool at room temperature until firm.
7. Once firm, cut them into little rectangles. (We cut 21 rectangles.)

For the Monster coating:

1. Melt approximately 1 cup of candy melts in a small bowl in the microwave at 50% power for 1 minute or at full power for 30-45 seconds. Stir and then continue microwaving at 50% power for 30 seconds or for 15 seconds at full power at a time until completely melted. (You can check the packaging instructions as well.)
2. Optional: Add approximately 1/2 teaspoon to 2 teaspoons cooking oil for a smoother finish. (The more you add, the smoother the finish and the longer the candy melts take to harden on the Rice Krispies, so go slowly!) Stir to combine.
3. Dip a quarter or half of the Rice Krispie treats into the candy melts and set on parchment paper.
4. Place candy eyes into the coating to create your monster faces. Press the eyes gently into the candy melt coating to help create the appearance of eyelids around the candy eyes.
5. Allow to cool at room temperature until the candy melts have completely hardened on the Rice Krispies treats (approximately 30 mins).