Preheat the oven to 400°F (200°C).
Spread the prepared vegetables on a large baking sheet.
Drizzle with the oil and toss to coat.
Roast for 20 minutes, carefully turn the vegetables over and return to the oven for a further 15 - 20 minutes until nicely roasted but not too brown. (At this point the vegetables can be cooled and chilled for 3 to 4 days.)
Meanwhile, warm the passata or tomato sauce in a medium saucepan over low heat.
Stir in the pesto.
Cook the pasta in a large saucepan in boiling salted water according to package directions. Drain and return to the saucepan.
Stir the passata or tomato sauce into the pasta in the large saucepan, along with the roasted vegetables.
Place half the pasta and vegetables in a large casserole.
Sprinkle with half the cheese.
Cover with the remaining pasta and vegetables.
Sprinkle with the remaining cheese.
Lower the heat in the oven to 375°F (190°C)
Place the casserole in the oven and bake for 15 to 20 minutes or until the cheese melts and is golden on top.