Generously season roast with coarse ground black pepper.
Place the onions in high sided roasting pan and place roast on top.
In a large bowl, mix the vinegar through bay leaves, pour into roasting pan.
Cover and cook for 3 to 3 1/2 hours, adding the prepared vegetables 45 minutes before the end of cooking time.
If desired the meat and vegetables can be removed from the cooking liquid when done and the liquid brought to a boil, reduced and then thickened with arrowroot starch or cornstarch. Serve the gravy over the cooked meat and vegetables.