Which brings me to Li-hing mui, (also pronounced lee-hee-mui) a salty, sweet, little sour, little licorice-flavored dried plum about the size of a large marble. Eat the 'meat' of the plum and spit out the seed. It's a Chinese snack and when I was a kid, it was one of many flavors of dried, preserved or otherwise salted seeds--my other favorites were rock salt plum and wet lemon peel (and yes, there is dried lemon peel as well).
In Hawaii, there are snack stores filled with glass jars of variations on seeds. The Crack Seed Center is a good example. The salt content is probably off the charts, but you usually eat just one, and one is really all you need. As a side benefit, one home remedy for head colds is 'hot li-hing-mui water' Drop a seed into hot water and drink it like tea. I've done this several times last week. Clears your sinuses and soothes your throat.
The li-hing apple slices are a good example of how the flavor plays well with others. You can find li-hing powder anywhere in Hawaii, at Marukai or other Hawaii/Japanese grocery stores or online at Amazon. You can also find li hing mui seeds in Chinese grocery stores. Just remember to eat it a little at a time, or take a very light touch with the powder. A little goes a LONG way.