Pre-heat oven on to 400° F. Season tomatoes with 1-tablespoon olive oil, salt and pepper; roast in the oven until blistered and slightly charred, set aside.
Bring a pot of water to a boil; cook pasta according to package directions. Meanwhile, in a skillet sauté onion with remaining olive oil for three minutes, add roasted tomatoes and cream, simmer for 5 minutes, smashing part of the tomatoes with the back of a spoon. Season with salt and pepper.
Drain pasta, toss with creamy tomato sauce, turn heat off and finish with cheese and basil before serving.
