1) Preheat the grill to 180C/Gas 4.
2) In a large bowl mix together the pork and all of the spices. Mix well until evenly distributed. Shape the mixture into 5 equal patties. Grill the patties on each side until cooked to desired doneness, about 4 minutes on each side.
3) In a large bowl, add olive oil, peppers, onions, salt and pepper, and toss together. Coat the mozzarella in the oil mixture, and transfer the slices to a large plate.
4) Using a grate on top of the grill, arrange the onions and sliced peppers. Close the grill and allow to cook for 1 to 2 minutes on each side.
5) Put the sliced peppers, onions and mozzarella on top of each meat patty. Close the grill and cook until the cheese melts, about 1 minute.
6) Tuck a sausage patty into each roll and arrange on a serving platter.
Cook's Note: After assembling each sandwich, gently squeeze the patty together so the bread absorbs some of the juice.