In a medium saucepan or Dutch oven, heat the olive oil over medium heat. Cook the onion and garlic, stirring often, until onions are soft but not yet browned. Add the red pepper flakes and stir for a minute, then follow with the tomato paste. Stir for another 2-3 minutes to heat and develop the flavor. Add the vodka next and stir well to scrape up any brown bits from the bottom of the pan. Add the tomato sauce and simmer. If a very smooth sauce Is desired, transfer to a blender, along with the cream, and puree until smooth. Otherwise, add the cream to the pot and stir to combine.

Bring a large pot of salted water to a boil and cook the pasta to al dente. Before draining, reserve about 1 cup of the pasta water. When ready to serve, toss the noodles with the sauce, adding the pasta water as needed to thin the sauce and create a nice smooth sauce. Garnish with grated cheese and serve.