In a large pot of salted boiling water, cook the rigatoni according to the package instructions until al dente. Drain and set aside, reserving about 1 cup of pasta water.

In a large skillet over medium heat, drizzle a little olive oil and add the Italian sausage. Cook until browned, breaking it into smaller pieces with a wooden spoon, for about 5-7 minutes.

Add the diced onion to the skillet. Sauté until it becomes translucent and fragrant, about 3-4 minutes. Then, throw in the minced garlic and stir for just another minute until you can smell that rich, nutty aroma.

Pour in the heavy cream and sprinkle the Italian seasoning. Stir well, allowing the mixture to simmer gently for about 5 minutes, thickening the sauce.

Toss the drained rigatoni into the skillet, mixing to coat every piece of pasta in the creamy goodness. If needed, add reserved pasta water a little at a time until you reach your desired sauce consistency.

Stir in the grated Parmesan cheese until melted and creamy. Season with salt and pepper to taste.

Transfer to a serving dish and sprinkle with fresh basil or parsley, along with extra Parmesan before serving.