1. Bring a large pot of salted water to a boil, then cook the rigatoni until al dente. Reserve 1 cup of pasta water, drain, and set aside.

2. Heat olive oil in a large skillet or Dutch oven over medium-high heat. Add the ground beef and cook for 6 to 8 minutes, breaking it apart, until browned.

3. Add the diced onion and cook for 3 to 4 minutes until softened. Stir in the garlic and cook for 30 seconds until fragrant.

4. Stir in the tomato paste and cook for 1 minute to deepen the flavor.

5. Add crushed tomatoes, beef broth, Italian seasoning, paprika, red pepper flakes, sugar, salt, and black pepper. Stir well.

6. Reduce the heat to medium-low and simmer the sauce for 12 to 15 minutes, stirring occasionally, until rich and slightly thickened.

7. Add the cooked rigatoni to the sauce and toss until well coated. Add reserved pasta water as needed to loosen the sauce.

8. Stir in Parmesan cheese, then serve hot with extra Parmesan and fresh parsley.