Spread the peanut butter over the surface of the tortilla.
Thinly slice the banana, then lay the slices over one half of the tortilla. Sprinkle the chocolate chips over the same half of the tortilla. Fold the tortilla to close over the banana and chocolate.
Cook the quesadilla in a skillet over medium-low heat until it's golden brown and crispy on both sides and the chocolate and banana slices are melty inside.