Sauté a soffrito made from finely chopped panetta, onion, carrot, celery and parsley in olive oil over medium-low heat until tender.
Then raise the heat to medium-low and add pieces of oxtail with crowding. Allow the oxtails to brown, turning them often, and seasoning with salt and pepper. Be careful not to allow the vegetables to burn; add a bit of water if need be.
Add wine and allow it to boil off completely, again turning the oxtail pieces. Then some crushed tomatoes and then enough water (or broth) to just cover the oxtail pieces, along with a bay leaf and a few cloves.
Cover and simmer until the meat is very tender, almost falling off the bone, anywhere from 2 to 4 hours, depending on the meat.
About 30 minutes or so before the dish is done, add a generous amount of chopped celery and allow it to cook along with the oxtail and other vegetables until everything is done.