In a large pot over medium high heat, heat the olive oil. Add the onions to the pot, and saute until soft. Add the beef to the hot oil. Season with salt & pepper, to taste.
2 tbsp olive oil, 1 large white onion, 1 lb lean ground beef, salt & pepper
Cook the beef, stirring and crumbling as it cooks, until it's completely browned- no pink remaining. Strain the meat, removing all excess grease, and return it to the pot.
Stir in the tomatoes, vodka, and chili flakes until evenly incorporated. Turn the heat to high, and bring the mixture to a boil. Stir the sauce until it's reduced by half, and slightly thickened.
1 28 oz can crushed tomatoes, 1/2 cup vodka, 1/4 tsp red chili flakes
Whisk in the cream until the sauce is smooth & it's evenly combined. Remove the pot from heat.
1/2 cup heavy whipping cream
Stir the cooked pasta into the pot and toss it in the sauce until the sauce has thickened slightly and begins to stick to the pasta.
4 cups cooked penne pasta
Sprinkle the still hot pasta dish with the shredded Parmesan cheese, and allow it to melt slightly. Ladle the pasta onto plates and serve immediately.
shredded Parmesan cheese