Prick the sausage in several places with a fork and place in a large pan. Add cold water to cover sausage and bring to a boil. Lower to a simmer and cook 40 minutes, then drain the sausage. Allow to cool, then peel and crumble out of casing.
On a clean cutting board, lay the veal out flat and cover the veal with the sausage in an even layer. Roll the veal up and tie in even segments with butcher's twine.
Heat the olive oil in the same large pan until almost smoking. Add the chopped onion and celery and cook until soft. Sear the veal roll on all sides in the pan so that it is evenly golden brown. Add the wine, bay leaf, parsley and tomatoes, lower heat to a simmer and cook 1 hour, adding more wine or water if necessary to keep moisture level consistent. Add the whole onions and carrots, adjust liquid level, and simmer for an additional 30 minutes. Season with salt and pepper to taste, remove from the pan and let rest 5 minutes. Remove the string and cut into thick slices. Serve immediately with pan juices poured over.
Recipe copyright 2000, Mario Batali. All Rights Reserved.