Begin by boiling a pot of salted water and cooking the fettuccine according to the package instructions. Once cooked, drain the pasta and set it aside.

In a large skillet, heat the olive oil over medium heat. Add the sliced chicken breast and sprinkle it with Cajun seasoning. Sauté until browned and cooked through, about 5 to 7 minutes. Remove the chicken from the skillet and set aside.

In the same skillet, add the sliced bell peppers, onions, and minced garlic. Stir and sauté until the vegetables are tender, adding a splash of water if needed.

Pour the chicken broth and heavy cream into the skillet, stirring to combine. Bring to a gentle simmer, allowing the sauce to thicken slightly.

Return the cooked chicken to the skillet and mix it into the sauce, allowing it to simmer for a few extra minutes.

Toss the cooked fettuccine with the sauce and chicken, ensuring everything is coated evenly. Season with salt and pepper to taste.

Plate the pasta and garnish with grated Parmesan cheese and fresh parsley.