COOK pasta as directed on package.
MEANWHILE, heat large nonstick skillet sprayed with cooking spray on medium-high heat. Add chicken; cook 5 to 7 min. or until chicken is done, stirring occasionally. Remove from skillet. Mix broth and flour in same skillet. Stir in Neufchatel, 2 Tbsp. Parmesan, garlic powder and pepper; cook 2 min. or until mixture boils and thickens, stirring constantly with whisk. Stir in chicken.
DRAIN pasta; place in large bowl. Add chicken mixture; toss to coat. Sprinkle with remaining Parmesan.