Creating these amazing peach turnovers is simple. Follow these steps for a delectable result:

1. Preheat the Oven: Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper.
2. Prepare the Filling: In a medium bowl, combine diced peaches, granulated sugar, cornstarch, cinnamon, and lemon juice. Mix until the peaches are well coated. Set aside.
3. Roll Out the Pastry: On a floured surface, roll out the thawed puff pastry sheets until they are about 1/8 inch thick. You can cut each sheet into squares (approximately 4-5 inches) or circles, depending on your preference.
4. Fill the Pastry: Place a generous tablespoon of peach filling in the center of each pastry square or circle.
5. Seal the Turnovers: Fold the pastry over to form a triangle (if using squares) or a half-circle (if using circles). Press the edges to seal and use a fork to crimp the edges for an attractive finish.
6. Prepare for Baking: Place the turnovers onto the prepared baking sheet. Brush the tops with the beaten egg mixed with milk for a golden finish.
7. Bake: Bake in the preheated oven for 25-30 minutes or until the turnovers are puffed and golden brown.
8. Cool: Once baked, remove them from the oven and allow them to cool slightly on a wire rack.
9. Optional Dusting: Dust with powdered sugar just before serving for an added touch of sweetness.

These simple steps ensure that your peach turnovers turn out incredible every time!