Typically Japanese zenzai is a dish served warm… sweetened red beans (azuki beans 小豆) made slightly soupy with piece of mochi 餅 (sticky rice cake). This makes for a delicious cold weather treat. But here in Okinawa… zenzai is usually served chilled! Okinawa zenzai is served cold topped with shave ice~~ this reminds me of Hawai’i! Who doesn’t order azuki beans in the shave ice?! I know I always do, much to my husband’s amusement. As a side note, shave ice is called kakigouri かき氷 in Japanese (I unfortunately on many occasions refer to it as “kaki-ice,” mixing my languages and often getting weird looks from everyone).
Not only this, but Okinawa zenzai is simmered with brown sugar cane (黒糖) to sweeten it instead of regular sugar; this gives a lot of depth to the taste! Another difference in Okinawa is that often red kidney beans are used instead of azuki beans. The reason for this is actually due to post-war, red kidney beans became common (and easier to get) because of the influence of the US military, rather than the smaller Japanese red azuki beans. Sometimes condensed milk is added as an extra topping, or various shave ice flavors might be used (matcha, strawberry… etc.).
There is a chain called 富士家 Fujiya that sets up stands in the shopping malls during the hot summer season. It is pretty famous in Okinawa, and the main shop is located in Tomari, Naha. I usually prefer the smaller places, but no matter what, this sweet frozen treat is a staple of Okinawan summers.
Here are pictures are of Okinawa zenzai from Fujiya and mainland Japan zenzai (these are taken during New Years for 鏡開き kagami-biraki, which is when the New Years mochi is opened).