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

In a large skillet, heat olive oil over medium heat. Add the chicken pieces and season with salt, pepper, and Cajun seasoning. Cook until the chicken is browned and cooked through, about 7-10 minutes.

Reduce the heat to low and add the garlic powder, onion powder, and paprika to the skillet. Stir for about 1 minute until fragrant.

Pour in the heavy cream and chicken broth, stirring to combine. Let it simmer for 5 minutes until slightly thickened.

Stir in the Parmesan cheese until melted and smooth. If using, add the fresh spinach and cook until wilted.

Add the cooked pasta to the skillet and toss to coat in the sauce. Adjust seasoning if necessary. Serve immediately, garnished with extra Parmesan if desired.