Ingredients:
- 6 Tablespoons unsalted butter (or 85g)
- 10 oz bag large marshmallows (about 40 standard or 283g)
- 1 Teaspoon pure vanilla extract
- 1/4 Teaspoon fine sea salt
- 10 Cups plain puffed corn (popcorn, air-popped)
- 3/4 Cup rainbow sprinkles (jimmies, or 120g)
- 1/2 Cup white chocolate chips (optional, for drizzling)
Instructions:
- Lightly grease a 9x13 inch baking pan and line it with parchment paper, ensuring an overhang on two sides for easy removal later.
- Ensure the 10 cups of popcorn are ready and placed in a very large bowl.
- Melt the butter in a large, heavy-bottomed saucepan over medium heat. Continue cooking, stirring occasionally, until the milk solids turn amber and the butter smells nutty (browning the butter).
- Reduce heat to low. Add the entire bag of marshmallows to the browned butter and stir constantly until completely melted and smooth. Do not allow the mixture to boil.
- Remove the pan from the heat immediately. Stir in the vanilla extract and salt until just combined.
- Gently fold in the rainbow sprinkles first, ensuring they are evenly distributed in the marshmallow mixture.
- Pour the melted marshmallow mixture over the prepared popcorn in the large bowl. Working quickly but gently with a greased spatula, fold until every piece of popcorn is fully coated.
- Transfer the mixture immediately into the prepared 9x13 pan. Lightly grease your hands or spatula and gently press the mixture evenly into the pan without packing it down too tightly.
- Allow the treats to cool completely at room temperature for a minimum of 1 hour.
- Optional: Melt the white chocolate chips in the microwave in 30-second intervals. Drizzle decoratively over the cooled treats and let the chocolate set for about 15 minutes.
- Lift the treats using the parchment overhang and cut them into even squares using a sharp knife.