Lightly grease your hands with butter or cooking spray. This will prevent the sticky mixture from clinging to your hands.
In a large microwave-safe bowl, combine the butter and marshmallows. Microwave on high for 1 to 2 minutes, stirring halfway through, until the marshmallows are melted and smooth.
0.25 cup Butter
Stir in the vanilla extract until well combined.
0.25 cup Butter
Add the popped popcorn to the marshmallow mixture and stir gently until the popcorn is evenly coated.
0.25 cup Butter
Working quickly, shape the popcorn mixture into balls using your greased hands. Place the formed balls on parchment paper to cool and set.
Notes
For extra flair, you can add sprinkles or chocolate chips to the popcorn mixture before forming the balls.