Cook Sausage: Heat olive oil in a large skillet over medium heat. Add the crumbled sausage and cook until browned and no pink remains. Stir occasionally to break the sausage into small pieces. Drain any excess grease.
1 tablespoon olive oil, 1 pound mild or spicy Italian sausage
Add Garlic and Seasoning: Add the minced garlic and Italian seasoning to the cooked sausage. Stir and cook for about 1 minute until the garlic is fragrant, being careful not to burn it.
2 cloves garlic, 1 teaspoon Italian seasoning
Add Pasta and Liquids: Pour the uncooked rigatoni into the skillet. Add the chicken broth, heavy cream, and marinara sauce. Stir to combine so the pasta is fully coated with the liquid.
1 pound rigatoni pasta, 3 cups chicken broth, 1 cup heavy cream, 2 cups marinara sauce
Cook Pasta: Bring the mixture to a boil, then lower the heat to a simmer. Cover the skillet with a lid and cook for 12–15 minutes, stirring occasionally to prevent sticking, until the pasta is tender.
Add Spinach: Once the pasta is cooked, add the fresh spinach to the skillet. Stir it into the hot pasta mixture and cook for 2–3 minutes, or until the spinach wilts.
2 cups fresh spinach
Season and Serve: Taste the dish and add salt, pepper, or red pepper flakes as needed. Serve hot, garnished with grated Parmesan cheese and fresh herbs, if desired.
Salt and pepper to taste, Optional: Red pepper flakes