Preparation
Combine chicken broth and cornstarch, stirring well; set aside. Place chicken between 2 pieces of heavy duty plastic wrap; pound to 1/2 inch thickness, using meat mallet or rolling pin. Coat with cooking spray; sprinkle with salt and pepper. Sprinkle 2 tablespoons breadcrumbs evenly over each chicken breast half; coat with cooking spray.
Place large nonstick skillet over medium heat until hot; add chicken. Cook 3 minutes on each side until done. Remove chicken from pan and keep warm.
Heat same skillet, coated w/cooking spray, over medium-high heat. Add mushrooms and shallots, cook 4-5 minutes or until tender, stirring occasionally. Add wine; cook 1 minute. Add chicken broth mixture; cook 2-3 minutes or until sauce is thickened. Removed from heat; add butter, stirring until butter melts.