Bring a large pot of salted water to a rolling boil. Add the rigatoni and cook until al dente, usually about 10-12 minutes. Reserve about a cup of pasta water, then drain the rigatoni and set aside.

In a heavy skillet over medium heat, drizzle olive oil and warm for a minute. Add the Italian sausage, breaking it into crumbles. Cook for 5-7 minutes until golden.

Once the sausage is browned, add the chopped onion and minced garlic. Sauté for 3-4 minutes until the onion is translucent and the garlic is fragrant.

Stir in the crushed tomatoes and tomato paste. Sprinkle in the dried Italian seasoning and mix well. Let simmer for about 15 minutes until it thickens.

Pour in the heavy cream slowly, stirring gently. If too thick, add reserved pasta water until you reach your desired consistency.

Add the drained rigatoni to the skillet, tossing to coat in the sauce. Cook for an additional 2-3 minutes on low heat.

Serve hot, garnished with fresh basil if using.