Boil a large pot of salted water and cook the fettuccine according to package instructions until al dente. Drain and set aside.

In a skillet, heat olive oil over medium heat. Add the sliced chicken, season with salt and pepper, and cook until browned and cooked through, about 5-7 minutes. Remove and set aside.

In the same skillet, add the onion, bell pepper, and garlic. Sauté until softened, about 3-4 minutes.

Stir in the Cajun seasoning, chicken broth, and heavy cream. Bring to a simmer and let cook for 5 minutes.

Add the cooked chicken and Parmesan cheese, stirring until the cheese is melted and the sauce is creamy.

Add the cooked fettuccine to the sauce, tossing to coat the pasta evenly. Adjust seasoning with salt and pepper if needed.

Serve hot, garnished with additional Parmesan cheese and parsley if desired.