Over the course of several weeks, these firm, under-ripe persimmons will transform, both ripening and dehydrating simultaneously, so that the sugars concentrate and crystallize, making a ridiculously tasty preserve.
firm, unripe Hachiya persimmons, ideally with their stems still attached and trimmed like a T (this provides more support for the string while hanging)
Timeline: ~6 weeks
Using a veggie peeler, peel the fruits' tough outer skin. Tie a string around their T stem and hang in a warm, dry, well ventilated area. Wait 5-7 days for their outer layer to dry and form a tough skin.
Using a very light touch, so not to break the outer layer of skin that has formed, begin a brief daily massage on each persimmon. The massaging helps break down the pulp and membranes inside. It also brings the fruits' fructose sugars to the surface.
After several weeks of light massaging daily, the dried fruit with continue to condense, reducing in size and darkening in color. The texture will change too, and you can massage with a firmer hand.
In about six weeks time, the outside of the fruit will become flecked with sugar crystals that look as if the dried persimmon were dipped in powdered sugar. This means your Hoshigaki is ready!
If the sugar does not bloom around six weeks, but the fruit is dark and firm, your environment may not be humid enough. Transfer the dried fruit to a large mason jar, or a zip-top bag and the sugar should bloom within two to three days.
Enjoy slices of your dried Hoshigaki with green tea for the ultimate pairing!