Preheat the oven to 200C or 180C Fan 0r 400F or Gas 6
In a large Casserole pot, heat the olive oil over a medium heat and soften the onions and carrots with a pinch if salt.
Add the garlic and cook for a further minute, then add the remaining vegetables. Gently soften for 8-10 minutes.
Stir in the tomato paste and half the Oregano. Cook for 2 minutes before adding the passata and vegetable stock.
Cook the sauce for 10 minutes to allow the sauce to thicken and the flavours to infuse.
Meanwhile, bring a pan of salted water to the boil, and cook the rigatoni for 6-7 minutes until the pasta has softened but not cooked.
In a small bowl combine the parmesan, remaining oregano, and breadcrumbs.
Drain the pasta and mix through the sauce. Transfer the rigatoni to a large enough ovenproof dish.
Top with shredded mozzarella and fill in any gaps with the parmesan breadcrumbs.
Bake for 20-25 minutes until the Pasta is cooked, the cheese is golden brown and bubbling.
