Prepare soup mix according to on-pack preparation instructions and set aside.
Combine the meats, bread, Parmesan, rosemary and seasonings in a large bowl and mix well. Form tablespoon measures into balls.
Heat half the oil in a frying pan and sear the meatballs in batches until golden. Set aside.
Heat remaining oil in a large saucepan, add onion and garlic, cooking for 3-4 minutes until tender. Stir in tomato paste and cook for a further minute.
Add stock, tomatoes, water and soup mix to the pan. Bring to the boil and reduce to a simmer. Return meatballs to pan and cook for a further 35-40 minutes or until meatballs and soup mix are cooked through. Stir in basil leaves and serve soup with grated Parmesan.