Preheat oven to Gas Mark 6, 200°C (400°F).
In a large bowl mix together the pork, breadcrumbs, cheese, egg, garlic, thyme, salt and pepper. With your hands shape the mixture into 16 small meatballs.
Put the meatballs, in a single layer, in an ovenproof casserole dish and drizzle over the olive oil. Toss gently. Place in the oven and cook until golden, about 15 minutes.
While the meatballs are cooking make the tomato sauce. In a small sauce pan, heat the chopped tomatoes, garlic, parsley, salt and pepper. Allow to simmer and reduce while the meatballs are cooking.
When meatballs are done, remove them from the oven and pour the tomato sauce over them. Mix to combine.
Heat the grill to high. Split the rolls lengthwise, but not all the way through. Place them on a baking sheets. Add four meatballs to each roll along with sauce, then top with the slices of cheese. Place under the hot grill until the cheese has melted, about 3-4 minutes.
Serve with a green salad.
Serve with hot dog/sub bread rolls, 100g grated low fat cheese and a green salad.