Mix sugar, corn syrup, and water together in a deep pan; bring to a boil. Heat to 250 degrees F (120 degrees C), or until a small amount of syrup dropped into cold water forms a rigid ball (hard ball stage), about 15 minutes.
Beat egg whites in a glass or metal bowl until stiff peaks form. Lift your beater or whisk straight up: the egg whites will form sharp peaks.
Slowly pour sugar mixture over egg whites while beating with an electric mixer. Beat until candy clings to a spoon and loses some of its shine. Spread candy mixture onto a sheet of waxed paper; sprinkle with confectioners' sugar. Generously spread peanut butter over candy mixture. Roll candy into one large roll; cut into 2 rolls. Slice each roll into desired pieces.
