Until I was properly introduced, in my notes I called these "sour strawberries."
That's not a bad description of the flavor of salak (1,500 riels for a bunch) once you peel off the prickly outer layer to reveal the rude bilabial fruit underneath. They're firm but moist; watch the pits.
Produce vendors near Psar Chaa
Siem Reap, Cambodia
(From a November 2006 visit)