Bring a large pot of salted water to a boil. Add the fettuccine and cook according to package instructions, usually about 8-10 minutes, until al dente. Drain and set aside.

In a large skillet, heat olive oil over medium heat. Season the chicken breasts with salt, pepper, and Cajun seasoning. Cook for 7-8 minutes per side until golden brown and cooked through.

In the same skillet, reduce heat and add minced garlic. Sauté for about a minute until fragrant. Pour in the chicken broth and bring to a gentle simmer. Stir in the heavy cream.

When the sauce thickens after about 3 minutes, mix in grated Parmesan cheese. Stir until the cheese completely melts and the sauce is creamy.

Slice the rested chicken and add it, along with the cooked fettuccine, to the skillet. Toss gently to evenly coat the pasta and chicken with the sauce.

Plating the pasta, garnish with additional Parmesan cheese or fresh parsley if desired. Serve immediately.