Preheat the oven to 180°C. Also, bring a large pot of generously salted water to boil.
Line a large roasting tin with parchment paper. Put the peppers, courgette, and onion in the tin and coat in oil. Season with salt ,pepper and Italian seasoning , then cook for 20 minutes, turning twice, until the veggies are tender and golden brown.
Add the cherry tomatoes, chopped tomatoes, garlic, and basil, then cook for 15 minutes. Add salt and pepper to taste.
Meanwhile, cook the pasta. You can add 4-6 tbsp of pasta cooking water to the vegetables to loosen the sauce.
Drain the pasta and stir it into the roasted veg. Stir through the mozzarella, red chilli flakes and pesto(if using) , top with the grated cheese, and return to the oven for another 10 minutes, until the cheese has melted.
Garnish with basil. Enjoy!