Preheat the oven to 170°C/Gas Mark 3/160°C fan oven.
Heat the oil and fry the onion and garlic for 4-5 minutes over a medium heat until softened but not brown. Add the beef and pork mince and cook stirring until browned.
Remove from the heat and drain off any excess fat and liquid.
Transfer the mince to a bowl, add the eggs, parsley, half of the cheese, and plenty of seasoning, mix well.
Cover the base of a shallow ovenproof dish with a layer of Tomato and Basil Sauce.
Fill each cannelloni tube with the mince mixture and place on top of the sauce.
Pour the remaining Tomato and Basil Sauce over the cannelloni and top with the rest of the mozzarella cheese. Cover loosely with foil and bake for 30 minutes. Remove the foil and cook for a further 15 minutes until the cheese is melted and golden.
Garnish with sliced tomato and fresh basil leaves before serving.