1. Coat the sliced chicken breasts with Cajun seasoning, salt, pepper, and 1 tablespoon olive oil. Let it marinate for 15 minutes.

2. Boil a large pot of salted water and cook rigatoni until al dente. Drain and set aside.

3. Heat remaining olive oil in a skillet over medium-high. Sear the marinated chicken in a single layer for 2-3 minutes per side until golden and cooked through. Remove and set aside.

4. In the same skillet, melt 3 tablespoons butter. Add garlic and smoked paprika; sauté 1-2 minutes until fragrant.

5. Pour in heavy cream. Simmer gently while stirring. Add Parmesan and mozzarella gradually, whisking until melted and smooth.

6. Season sauce with salt, pepper, and nutmeg. Simmer on low for 5 minutes, stirring occasionally.

7. Return cooked chicken to the sauce. Add rigatoni and toss to combine. Let simmer for 2-3 minutes so flavors meld.

8. Taste and adjust seasoning. If too thick, add pasta water or milk to loosen.

9. Serve hot, garnished with parsley, Parmesan, and red pepper flakes.