Cut out the bones and cut the rest into large cubes. Heat the oil in a saucepan and fry the meat, also the bones, salt and pepper and add the tomato paste, toast briefly. Add the onions (whole) to the pot, add bay leaves, rosemary, peppercorns and pour red wine and water on top. The whole thing should be about 2/3 in the liquid, add wine or water if necessary.
Cook on a low heat for about 90 minutes, stir occasionally, season to taste again, season if necessary and finally add the vinegar to the sauce and mix!