Wash inside of hens and dry thoroughly. Cut off wings, chop and reserve. Halve hens by cutting through back of either side of back bone.
Preheat oven to 400 degrees F. Heat 1/4 cup clarified butter over high heat in baking dish. Add wing pieces and fry.
Stir in carrot, onion and celery and continue to fry. Place hen halves on bed of vegetables and add sherry. Season with salt and white pepper and baste with a little clarified butter. Roast on middle shelf of oven for 45 minutes.
Melt scant 1/4 cup clarified butter in saucepan. Stir in flour and cook until it browns, but don't let it burn. Add madiera and veal stock. Stir in jelly and juice from truffle. Bring to a boil, then simmer over low heat for 40 minutes or until hens are cooked.
Remove hens to a warm platter. To finish sauce, add red wine and lemon juice to pan. Pour this over vegetables in roasting pan, bring to boil, skim and sieve into clean pan. Discard vegetables. Sprinkle hens with grapes and sliced truffle. Garnish with parsley. Serve with sauce.