Instructions:

1. Prepare Popcorn: Pop 12 cups of popcorn and set aside.
2. Microwave Caramel Mixture: In a microwave-safe bowl, combine brown sugar and butter. Microwave for 2 minutes or until the mixture is melted and smooth.
3. Add Marshmallows: Add 9-10 marshmallows to the melted brown sugar and butter mixture. Microwave again until the marshmallows are completely melted, stirring as needed to ensure a smooth consistency.
4. Combine with Popcorn: Pour the marshmallow caramel mixture over the popped popcorn. Gently toss and stir, ensuring the popcorn is evenly coated.
5. Set and Enjoy: Allow the Marshmallow Caramel Popcorn to cool and the caramel to set. Serve and enjoy this delightful treat for a perfect blend of sweetness and crunch!

Note: You can add a sprinkle of sea salt or your favorite nuts for an extra flavor dimension.