Cook the penne pasta according to package instructions until al dente. Drain and set aside.

In a large bowl, toss the chicken pieces with Cajun seasoning until well coated.

In a large skillet, heat the olive oil over medium heat. Add the seasoned chicken and cook until browned and cooked through, about 6-8 minutes. Remove the chicken from the skillet and set aside.

In the same skillet, add the diced onion and sliced bell pepper. Sauté for about 4-5 minutes until the vegetables are softened. Add the minced garlic and cook for an additional 1 minute.

Pour in the chicken broth and bring to a simmer. Stir in the heavy cream and let it cook for 2-3 minutes until slightly thickened.

Add the cooked chicken back into the skillet, followed by the cooked penne pasta. Stir in the grated Parmesan cheese until melted and combined. Season with salt and pepper to taste.

Serve hot, garnished with fresh parsley.