1. Bring a large pot of salted water to a boil and cook the penne until al dente. Reserve 1/2 cup of pasta water, then drain and set aside.

2. Season the chicken pieces with Cajun seasoning, paprika, salt, and black pepper until evenly coated.

3. Heat olive oil in a large skillet over medium-high heat. Add the chicken and cook for 5 to 7 minutes, stirring occasionally, until golden and cooked through. Transfer the chicken to a plate.

4. In the same skillet, melt the butter. Add the diced onion and sliced red bell pepper, then cook for 3 to 4 minutes until softened.

5. Stir in the minced garlic and cook for 30 seconds until fragrant.

6. Pour in the chicken broth and scrape up the browned bits from the bottom of the skillet.

7. Lower the heat to medium and stir in the heavy cream. Let it simmer gently for 2 minutes.

8. Add the Parmesan cheese and stir until the sauce is smooth and creamy.

9. Return the cooked chicken to the skillet, then add the drained pasta. Toss everything together until evenly coated.

10. Add a splash of reserved pasta water if needed to loosen the sauce.

11. Taste and adjust seasoning if needed, then sprinkle with fresh parsley and serve hot.