In a large pot, melt the butter over low heat. Once melted, add the marshmallows and stir constantly until they are completely melted and fully combined with the butter. Make sure the mixture is smooth and free of lumps.

Remove the pot from the heat. Add several drops of yellow food coloring and mix well. Then, add red food coloring one drop at a time, mixing after each drop, until you reach your desired pumpkin color. I find about 4 drops of red and 12 drops of yellow create a lovely pumpkin orange, but adjust as you like. Make sure the color is evenly blended throughout the mixture.

Immediately add the rice cereal to the colored marshmallow mixture. Stir gently with a spatula or large spoon until all the cereal is evenly coated. Work quickly, as the mixture becomes harder to stir as it cools.

Coat both sides of your hands generously with neutral oil or melted butter to prevent sticking. While the mixture is still warm, scoop out portions and roll them into small balls, about the size of a golf ball. Place each ball on parchment paper. Reapply oil or butter to your hands between rolling each ball, as needed. I like to be generous with the oil—it's the secret to easier shaping and less mess!

While the rice balls are still warm and pliable, gently press a Mini Rolo into the top of each ball to act as a pumpkin stem. Place a green M&M next to the Rolo to mimic a leaf. If the treats cool before you're finished, use the end of a thick marker or an apple corer to make a small indent in the top for the Rolo. This step adds a lot of charm to your treats!

Allow the decorated treats to cool at room temperature until they are firm. They can then be served or stored in an airtight container.