Preheat your oven to 400°F (200°C) and line two baking sheets with parchment paper.

In a small bowl, whisk together one large egg with 1 tablespoon of water.

Roll out the thawed puff pastry to an even thickness of about 1/8 inch and cut into 5x5 inch squares.

Place approximately 1½ tablespoons of cherry pie filling in the center of each pastry square and brush the egg wash around the edges.

Fold each square in half diagonally to form a triangle and use fork tines to seal the edges.

Bake the turnovers for 18-20 minutes until golden brown.

Allow to cool on the baking sheets for 5 minutes before transferring to a wire rack.

Mix powdered sugar, water, and vanilla extract in a bowl and drizzle over cooled turnovers.