Just around the corner street from the Marriot resort in Waikiki is a little place called Waiola Shave Ice (525 Kapahulu Ave, 735-8886).
Shave Ice is to Sno Cones what creme brulee is to vanilla pudding. You don't have to go all the way to the North Shore and stand in line forever to get the best Shave Ice in Hawai'i.
Whenever we go back home, my young daughter won't let us drive past without stopping.
Have it with the ice cream on the bottom. And remember, you're in the islands, so go try some of the local flavors. For a true island-style treat, get it with Azuki beans (they're sweet) on the top.