Bring a large pot of salted water to a boil. Cook the pasta according to package directions until al dente. Reserve ½ cup of the pasta water, then drain and set aside.

In a large skillet, heat olive oil over medium-high heat. Add the sliced sausage and cook until browned, about 4–5 minutes. Remove and set aside.

In the same skillet, add the diced onion and sauté for 2–3 minutes until softened. Stir in the minced garlic and cook for another 30 seconds.

Reduce heat to medium-low. Stir in the tomato paste and Cajun seasoning, cooking for 1 minute. Pour in the chicken broth and heavy cream, stirring to combine. Let simmer for 2–3 minutes until slightly thickened.

Return the sausage to the skillet. Add the drained pasta and Parmesan cheese. Toss everything together, adding a splash of reserved pasta water if needed to loosen the sauce.

Garnish with chopped parsley and extra Parmesan if desired. Serve hot and enjoy!