Place chicken breast halves between sheets of waxed paper or plastic wrap. Pound slightly with mallet. Sprinkle with salt and black pepper. Heat 1T each of oil and butter in large skillet. Cook chicken over high heat for 4 minutes on each side. Do not cook longer or they will be overcooked and dry. Transfer to warm serving platter. Add chives or green onion, lime juice and brandy, if used, parsley and mustard to pan. Cook 15 seconds, whisking constantly. Whisk in broth. Stir until sauce is smooth. Whisk in remaining butter and oil. Pour sauce over chicken. Serve immediately.