Leek Casserole
2 Combine the leeks, celery, carrot and potato with the chicken stock (keep a small amount for thickening) and simmer until vegetables are tender (about 20 minutes).
3 Empty into a casserole dish, add tomatoes and parsley and season to taste with black pepper. Cover and cook for 30 minutes.
4 Thicken to your liking (you may not want to thicken it at all) with reserved chicken stock and cornflower