Bring a large pot of lightly salted water to a boil and cook the penne pasta until al dente, then drain and set aside.
Heat olive oil in a large skillet over medium heat and sauté the chopped onion until translucent, about 5 minutes.
Add minced garlic and red pepper flakes to the skillet and cook for 1 minute, stirring constantly.
Pour in vodka and simmer for 2 to 3 minutes to cook off the alcohol and concentrate the flavor.
Stir in crushed tomatoes, reduce heat to low, and let the sauce simmer for 10 minutes, stirring occasionally.
Add heavy cream and grated Parmesan cheese to the sauce, stirring until smooth and slightly thickened.
Add the cooked penne pasta to the sauce and toss to coat evenly.
Season with salt and freshly ground black pepper to taste.
Sprinkle chopped fresh basil over the pasta, toss gently, and serve immediately.