Start with thawing the puff pastry till it's soft but still cold.
Heat a pan over medium heat.
Add the butter, chopped apples, brown sugar, and two tablespoons of water.
Cook the apples till they are soft.(Check the video and photos)
Cut the puff pastry into equal squares.(or use precut ones)
Add a spoonful of apple mixture in the middle and fold the pastry diagonally. Make one or two incisions(cuts) so that the steam can escape.
Using a fork, seal the sides.Using a brush, brush the apple trunovers with beaten egg.
Preheat the Air fryer for 2 minutes at 180C or 365F
Place the turnovers in a single layer.
Set the temperature at 180 C or 465F for 6 minutes.