Place salad dressing in a small resealable plastic bag; add the chicken. Seal bag and turn to coat; refrigerate for 15 minutes. Drain and discard marinade.
Cook fettuccine according to package directions. Meanwhile, in a large skillet, cook chicken over medium heat until no longer pink; remove and keep warm.
In the same pan, melt butter; whisk in the flour, Italian seasoning, garlic powder and pepper. Stir in cream. Bring to a boil; cook and stir until thickened. Stir in cheese and chicken; heat through. Drain fettuccine. Serve chicken mixture with pasta. Yield: 2 servings.