Spread peanut butter on both slices of bread and place the popcorn onto one slice, making sure it sticks. The popcorn doesn't have to be salted, but I preferred it cause it gave it a little pizazz. Place the slice without popcorn on the slice with popcorn, pressing down lightly (or firmly for a bubble-wrap experience).
Source of recipe: When I was little my dad didn't have a ton of money to make us three kids pb and j's like other kids, so he got a little creative. I really looked forward to having these every time I went to his house.