Cut beef tenderloin into six 1- inch-thick slices.
Place steaks on a well-greased rack in a shallow roasting pan. Broil steaks 6 inches from heating element 10 minutes on each side or until desired degree of doneness.
Place each fillet on a slice of toast. Transfer to a warm serving platter, and sprinkle with salt and pepper. Drizzle with melted butter, and sprinkle with chopped parsley. Garnish platter with lemon slices, if desired.