Cut the cooked squid or octopus into thin crosswise slices and set aside. Wash luau leaves thoroughly; remove stems and fibrous parts of veins. Place washed leaves in large saucepan; add water. Bring to a boil, lower heat, and simmer for 1 hour, stirring frequently. Drain luau leaves thoroughly; stir in coconut milk, salt, and squid. Heat but do not boil.