Last weekend, I managed to score a good price for a mamey sapote. This fruit, about the size of a small melon, doesn't look like much from the outside. Heck, I often see it piled up with potatoes, given the appearance. But open it up, and it is a world of a difference from a potato.
One has to be careful about eating this ripe (it turns soft and yielding), as the unripe fruit, like an unripe persimmon, as an astringent sap. The actual fruit is sweet, and a texture reminiscent of a well cooked sweet potato, albeit with some graininess. I believe they make this into a popular ice cream in India, called a chikoo flavor.