First, heat a medium skillet or griddle over medium heat, spread one tablespoon of peanut butter onto each slice of bread. Place the banana slices onto the peanut buttered side of one slice, top with the other slice and press together firmly.
Spread butter on the outer side of the bread slices and fry the sandwich until golden brown on each side. About 2 minutes per side.
Notes
This sandwich is highly customizable! You can use any of the nut butter you'd like and whatever fruit you prefer.