Preheat the oven to 375*F.
Lay out one sheet of puff pastry and spread the Nutella evenly, leaving about 1/2" at the edges.
Microwave the peanut butter on high for 30 seconds-1 minute, ot until the peanut butter is smooth and melted.
Arrange the banana slices evenly on the Nutella, the pour the peanut butter on top of the banana slices.
Top with the other sheet of puff pastry.
Sprinkle evenly with the turbinado sugar.
Bake for 18-25 minutes, or until the pastry has puffed and lightly browned.
Remove from the oven and let cool before serving.