In a popcorn maker or large pot, pop the popcorn kernels according to the package instructions. Set aside in a large mixing bowl.
In a medium saucepan over medium heat, melt the butter. Once melted, add the mini marshmallows and stir constantly until they are fully melted and smooth.
Remove the pan from heat and stir in the vanilla extract and salt until well combined.
Pour the melted marshmallow mixture over the popped popcorn. Use a spatula or your hands (coated in butter or oil to prevent sticking) to gently fold the mixture until all the popcorn is coated.
If using, sprinkle the chocolate chips over the warm popcorn and gently mix so they melt slightly and create a drizzle. Add colored sprinkles on top for extra fun and visual appeal.
Spread the marshmallow popcorn onto a large baking sheet lined with parchment paper. Let it cool for about 30 minutes for the marshmallow to set slightly.
Once cooled, break it into clusters and enjoy your delicious Marshmallow Madness Popcorn!
Notes
Use butter or oil on your hands to prevent sticking when mixing.