Place chicken first in flour, egg and then bread crumbs. Fry in oil until cooked. Drain on paper towel. Melt 5 tablespoons butter in a 2 quart pot, add sliced onion and mushrooms. Cover and cook until tender.
Remove from heat and add 1/4 cup white wine and allow favors to marinate. Melt 1/4 pound butter in skillet. Add chicken broth and 1/2 to 1 cup white wine, stir.
Place chicken cutlets in skillet. Top each cutlet with shredded Mozzarella. Pour mushrooms and onion mixture over cutlets. Cover skillet and heat just until Mozzarella is melted.
