Fry chicken till golden then put in bottom of chosen baking dish
Fry leeks in a little butter set aside
Fry 2 sliced celery in same butter set aside
Add tbsp butter and 2 tbsp flour to pan make rue add chicken stock and creamand tbsp mustard pour over chicken peices
Then put fried leek on top of chicken and sauce
Boil potatoes with the last sliced celery in same pan then mash up and mix in the set aside celery ...cover leeks with mash mixture top with salt pepper and sprinkle of cheese if you wish cook 30 ish mins 180 electric fan ....serve piping hot with chosen vegg