Preheat oven to 190 degress C
Heat the olive oil in a large oven proof sauté pan over medium heat, add the onions and garlic and cook for about 5 minutes until translucent. Add the red pepper flakes and cook for 1 minute more. Add the vodka and continue cooking until the mixture is reduced by half, about 5 minutes more.
Place tomatoes in the pan, add 2 teaspoons salt and a pinch of black pepper. Cover the pan with a tight-fitting lid or foil and place it in the oven for 1½ hours.
Meanwhile, bring a large pot of salted water to a boil and cook the pasta al dente. Drain and set aside.
Place the tomato mixture in a blender or food processor, add fresh basil and purée in batches until the sauce is a smooth consistency. Return sauce to the pan.
Reheat the sauce, add heavy cream, simmer for 10 minutes. Toss the pasta into the sauce and cook for 2 minutes more. Stir in a generous handful of grated cheese. Serve with an additional sprinkle of cheese
