Lay chicken between 2 sheets of waxed paper or place inside a gallon sized freezer bag, and flatten breast with a meat pounder until thin (approx. ½” thick) Dredge lightly with flour. Melt the butter in a skillet, add the mushrooms, and saute over medium heat until nicely browned, abut 10 minutes. Remove the mushrooms from the skillet and set them aside. Add chicken breast to skillet. Saute chicken over med. High heat about 2 minutes on each side. Remove it to a platter and keep warm. Add the garlic herb sauce mix to skillet, stir in water and Marsala and bring to a simmer. Add chicken and mushrooms into sauce and simmer about 3 minutes. Serve sauce over chicken and side of roasted garlic and parsley linguine or pasta of choice.