1. Split the banana lengthwise into two halves. Spread one half with the peanut butter.
2. Sandwich the two banana halves together and wrap the entire banana in plastic wrap (or you can cut bananas into 1-inch wheels and carefully store in a plastic bag or container).
3. Freeze until solid, at least 4 hours.
Note: You can also add chopped strawberries for a PB&J banana treat. Or sprinkle chocolate chips in the middle before closing the banana halves.