Method
Place the mince, onions and mushrooms in a bowl add the salt, pepper and herbs and mix well. Open the roast spread the beef mix over the pork, roll up the roast and tie it well. Usually I use three ties to hold it. Rub the mustard over the outside of the pork place on a rack in the dish add 2 cups of water or white wine to the dish. Place in a preheated oven 230°c for 20 minutes or until browned then turn down to 180°c. Cook at 180°c at 25 minute per ½ kg. Again rest for 15 minutes then slice.