While living in Hainan, I realised that there is in fact a food here that seems to be unique. They call it 炒冰 (literally ‘fried frost’)。 You won’t likely find it in the dictionary. The customer selects some fruits they like. Those fruits are then put into a blender to make a thick liquid. That liquid is then fried, then frozen. It is a lot like a Icee or a bowl of ice with flavouring. However, the flavour is a lot stronger. It also lacks much of the refined sugar of similar dishes westerners have tried (usually it is the Chinese version of dishes that have tons of added sugar).
Thus, besides Hainan Fried Rice (which is the same as Singapore Fried Rice) and Wenchang Chicken, Hainan still has something that doesn’t seem to generally be available anywhere else. These 炒冰 stands on the street at night are common, with 5-10 in a row right next to each other. Plenty of customers as well.