Melt smart balance in saute pan. add mushrooms, garlic and shallot. Saute 5 minutes until mushrooms are done.
Stir marsala into mushrooms and stir up any browned bits; simmer and reduce marsala by half.
whisk cornstarch into a bit of the chicken broth until smooth; add remaining chicken broth. Pour this into reduced marsala and bring to boil; simmer 2-3 minutes to thicken sauce. Turn off heat and cover pan.
heat a large skillet to medium heat.
Season cutlets with salt and pepper to taste.
Spray cooking spray into the pan and cook about 2 -3 minutes per side. Do this in batches, if necessary.
Place chicken into marsala-mushroom sauce. Allow to simmer several minutes until chicken is cooked through and sauce is thickened.
Serve chicken over cooked pasta or brown rice; garnish with parsley.