In a microwave-safe bowl, melt the marshmallow or vanilla melts according to instructions on package.
Add 8 cups of popcorn to a large bowl and pour in the marshmallow coating. Stir until well coated.
Add the cotton candy and gently mix to distribute throughout the popcorn.
Spread popcorn out on lined baking sheet and add the sprinkles on top. Allow to cool.
In two separate bowls, melt the blue and pink candy coating.
Divide the remaining popcorn equally between two bowls - 2 cups in one bowl, 2 cups in the other.
Pour the blue coating over the popcorn in one bowl and the pink over popcorn in the other bowl.
Stir until well-coated and spread the popcorn out on another lined baking sheet.
Combine the white, pink and blue popcorn and enjoy!
Notes
Work Quickly with Marshmallow Coating: Once you've melted the marshmallow or vanilla candy melts, work quickly to coat the popcorn before the mixture begins to set. Use a spatula or large spoon to evenly distribute the coating, ensuring that all popcorn kernels are coated for a uniform flavor.
Add Cotton Candy Carefully: When adding the torn pieces of cotton candy to the coated popcorn, do so gently to avoid crushing the cotton candy into small pieces. The torn cotton candy adds a fun and colorful element to the popcorn, so try to keep the pieces relatively intact for visual appeal.
Ensure Even Coating with Candy Melts: When melting the blue and pink candy melts for the popcorn drizzle, ensure that they are melted to a smooth consistency. Use a spoon or fork to drizzle the melted candy coating evenly over the popcorn, moving your hand in a back-and-forth motion for a decorative effect. Aim for even coverage to ensure that each popcorn kernel gets a taste of the colorful candy coating.