Saute the leeks and celery in a little oil for 5 min. Add 2/3 cup
water. Season, cover, and cook until the vegetables are tender. Put
them into an ovenproof baking dish. In another pan, melt the butter.
Stir in the flour, mustard powder and turmeric. Cook for 2 min.
Gradually add the milk, stirring all the time to make a smooth sauce.
Pur the sauce over the leeks and celery. Mix the cheese and
breadcrumbs together and sprinkle them over the top. Brown in the oven
at 375° for 15 min.
