Remove any unpopped kernels from the popcorn. Spray a large mixing bowl lightly with cooking spray. Add the popcorn to the bowl.

In a large saucepan, over medium-low heat, melt marshmallows and butter, stirring constantly until fully melted.

Add enough food coloring to the marshmallow mixture to get a nice neon green color. Pour over the popcorn and stir until the popcorn is fully coated. Stir in the sprinkles.

Spray your hands with cooking spray to prevent sticking. Take a handful of the popcorn at a time and form into balls. Let them cool then display on a platter and serve or wrap in plastic wrap to store at room temp if making them ahead of time.