Fill a large pot with water, add salt, and bring it to a rolling boil. Once boiling, add the fettuccine and cook until al dente, about 8-10 minutes. Drain and set aside.

Slice the chicken breasts into thin pieces and season both sides with salt and black pepper.

In a large skillet, heat olive oil over medium-high heat. Add the sliced chicken and cook until golden brown and cooked through, usually about 5-7 minutes per side.

In the same skillet, add diced tomatoes and minced garlic. Sauté for about 2-3 minutes until the tomatoes soften and the garlic becomes fragrant.

Pour in the heavy cream and chicken broth, followed by Cajun seasoning. Stir well and bring to a boil, allowing it to simmer for a couple of minutes.

Gradually stir in the grated Parmesan cheese, allowing it to melt. Simmer for an additional 3-5 minutes until the sauce thickens.

Toss the cooked fettuccine and seared chicken into the Cajun sauce, coating everything thoroughly. Serve hot, garnished with fresh chopped parsley.