Preheat the oven to 400°F. Line a baking sheet with parchment paper.
Cut puff pastry into 4 pieces.
Thinly slice (⅛”) apples. You will need 4 slices for each tart.
Drizzle the honey onto the baking sheet in 4 spots. Sprinkle each honey spot evenly with cinnamon. Lay 4 slices of apple on each spot.
Place the puff pastry square on top of the fruit and honey, gently pressing down to seal the edges. Use a fork to crimp the sides.
Mix the egg and water in a small bowl. Brush the puff pastry with the egg wash.
Bake for 15-20 minutes until the puff pastry is golden brown. Let the tarts cool for about 5 minutes. Then carefully flip each one over onto a serving plate. Sprinkle the tarts with powdered sugar and serve!
Notes
Note: Serve with a scoop of vanilla ice cream for an extra treat!