Kwai muk is a small, tart fruit from an evergreen tree of the mulberry family (Moraceae), a close relative of the jackfruit and breadfruit. Native to southern China and cultivated across Southeast Asia, it produces irregular, thin-skinned fruits about 2.5–5 cm across that ripen to a soft, dull orange to reddish-brown. The juicy pulp is subacid to sharply sour with a fragrant, apricot-like tang, and the fruit is eaten fresh, stewed, preserved or dried into a chewy, raisin-like sweet.