Wrap 1 piece of veal around 2 basil leaves and 1 piece of bocconcini, ensuring filling is enclosed. Secure with a toothpick.Repeat process with all remaining veal, basil leaves and bocconcini (other than the basil for serving).
Heat half the oil in a large non stick frying pan over medium-high heat. In batches, cook the veal for 2 minutes each side or until completely brown. Transfer to a plate and cover to keep warm.
Heat remaining oil in pan over medium heat. Add onion and cook, stirring constantly, for 5 minutes or until soft. Add garlic and cook for 1 minute or until fragrance releases. Add pasta sauce and stock and bring to the boil. Once boiling, reduce heat to low.
Return veal, and any juices, to pan. Cook, turning occasionally, for 5 minutes or until veal is cooked through and bocconcini just begins to melt. Season with salt and pepper.
Serve involtini and sauce topped with fresh basil leaves.