Preheat oven to 400°F. Line a baking sheet.

Mix chicken, veggies, soup, cheese, salt, and pepper in a bowl.

Unfold puff pastry and cut into four squares.

Spoon filling onto one half of each square, leaving edges clear.

Fold pastry over filling and press edges with a fork to seal.

Brush tops with beaten egg.

Bake 18–22 minutes until golden.

Let cool for 5 minutes before serving.