Place the tomatoes onto a flat baking tray or roasting dish. Drizzle with a small amount of oil and season lightly with salt and pepper. Place in the oven and roast for 1 hour. Remove from the oven and leave to cool down.
Meanwhile bring a large saucepan of lightly salted water to the boil. Add in the spaghetti and cook according to the packet instructions.
Drain the spaghetti and add this to the cream mixture. Next add in the slow roasted tomatoes, lemon zest and the chopped parsley. Continue to simmer for 4-5 minutes.
Add in half of the grated parmesan cheese and mix well.
Season lightly with salt and cracked black pepper and ensure that everything is piping hot.
Transfer to serving dishes and sprinkle with the remaining parmesan. Serve with some crisp garlic bread.