Heat a little olive oil in a large frying pan. Season the rabbit pieces and brown thoroughly over a medium flame, about 10 minutes, turning regularly.
While the rabbit is browning, sweat the pancetta in a large casserole. When it renders a little fat, add the sofritto and sweat for 10 minutes. Add the tomato pieces and wine, then turn up the heat and boil for a few moments. Turn the heat down and add the rabit pieces, by now nicely golden brown. Add the bay leaves and sage leaves. Cover and simmer for 45 minutes (do not skim). The rabbit will have shrunk and be very tender. Adjust the seasoning.
It is now ready to serve as a casserole. If you wish to use it as a pasta sauce, allow to cool completely, then with your hands pull the meat off the bones, shredding it as you do, and returning it to the sauce. Reheat with large knob of butter, extra seasoning, and toss with cooked pappardelle, adding grated Parmesan.