In a small saucepan, heat juice from 2 lemons, zest from 1 lemon, butter, wine and stock or water and bring to a boil. Reduce and simmer for 10 to 12 minutes or until reduced by about half. Meanwhile, heat broiler to high and grease a sheet pan with cooking spray. Season fish with salt and pepper and broil on high for 6 to 10 minutes or until flakey and cooked all the way through. Cut remaining lemon into thin slices. Serve each filet with a generous drizzle of sauce, sliced lemon and a sprinkle of parsley.