In a pan, heat up the oil over a medium heat, add the peeled and chopped onion, and fry until golden.
Add the peeled and chopped garlic, frozen vegetables and shredded cooked turkey together with the bay leaves and chicken stock.
Leave to cook until the liquid is evaporated.
In a small bow, mix the cornflour with the milk, and pour it over the turkey and vegetables.
Stir until it thickens into a sauce that coats well the turkey and veggies.
Season with salt and pepper to taste, remove the bay leaves and leave to cool completely.
Preheat the oven to 180 degrees Celsius (350 Fahrenheit).
Roll the puff pastry, and cut it into 6 squares.
Add one tablespoon of the turkey filling in the centre of the pastry square, bring the corners of the pastry together to form a triangle, and press with a fork to seal the edges. Repeat with all the pies.
Beat the egg, and brush each pie with it, then make 2 small cuts on top to allow the steam to be released while baking.
Line 2 or 3 baking trays with non-stick paper and bake for about 25 minutes until golden.