Pour 3 cups water, white wine and vermouth into a pot and add bay leaf and peppercorns. Bring to a boil and then remove bay leaf and peppercorns. Return to a boil and add carrot, fenel and celeriac. Cook until desired doneness. Reserve stock. Return stock to a boil. Add citrus juices and half and half. Reduce to sauce consistency. Add the blanched vegetables. Bring to a boil and remove from heat. Add the endive. Swirl in the butter and then the mustard. Season with salt and pepper to taste. Set aside and keep warm. Do not allow the sauce to boil again. Heat the clarified butter in skillet. Dust each fillet with flour and fry until done about 3 minutes per side. Place fish on plate and serve sauce over.