Placed sliced onions in bottom of roasting pan. Place roast on top of onions. Mix sauces together and spread over roast. Bake, covered, all day (at least 5 hours) at 225 degrees or in a crockpot for six hours, or until tender. One half hour before serving, shred meat, remove bones and put back in sauce. Continue cooking for 1/2 hour. Serve on buns. Venison can also be used.