1 (3.5-ounce) package butter-flavored microwave popcorn
1/4 cup unsalted butter
4 cups miniature marshmallows
1 cup dry roasted peanuts
Pop popcorn according to package directions.
Meanwhile, lightly coat a 13 x 9 x 2-inch pan with vegetable cooking spray.
Melt butter in a large saucepan over medium heat. Add marshmallows and stir until melted and smooth. Add popcorn and peanuts. Gently stir until thoroughly combined. Pour mixture into prepared pan and flatten surface with a spatula. Allow to set up for 1 hour before cutting into squares.
Makes 16 bars.