Refrigerate ingredients then LAYER in chilled glass by carefully pouring in the following order.
Easy to layer but hard to drink. Very sweet.
Named after and inspired by the red and green running lights which respectively mark the 'Port' (left-hand) and 'Starboard' (right-hand) sides of a ship. The red light is called Port side because port wine is red. The original name for the opposite side was Larboard, but over the years was corrupted to Starboard.