In the same pot, brown the remaining mushrooms. Add more oil as needed. Deglaze with the wine and let reduce by half. Add the veal stock and mustard. Return the meat to the pot. Bring to a boil. Cover and bake in the oven for 3 hours or until the meat is fork-tender and the sauce has been almost completely absorbed (see note). Remove the bone from the meat. In the pot, shred the meat, removing any excess fat. Compost the bone and fat.
