Fry the chicken in a little oil until golden. Then add chopped leeks for a further 2 minutes.
Add the Chicken Tonight Creamy Mushroom Sauce and simmer for 5 minutes.
Place in an ovenproof dish and cover the dish with the readymade pastry, cutting to the shape of the dish and using any excess to decorate the top of the pie, if desired, and brush with the beaten egg.
Place in a preheated oven at 170 degrees and cook for 20 minutes or until the pastry is a golden colour.
Great with chips.