Remove the skin for the chicken breasts and cut in half, roll them in flour and brown them in a little oil for 3 – 4 minutes.
In another frying pan, sauté the leek and onion in a little oil for 5 minutes until soft and golden.
Put the chicken into a casserole together with all the vegetables and the stock. Cook in an oven preheated to 180oC/350oF/Gas mark 4 for 1 hour, stirring half way through the cook.
Take the chicken off the bone and chop it up in small pieces, add to the casserole dish again and serve with potatoes.