I began consuming jicama several years ago when I moved from Missouri (where I had never seen them before) to Texas, where it was plentiful in the supermarkets. Native to Mexico and Central America, it is also known as Mexican Potato and Yam Bean. While I find it in the stores around here year-round, Diana Kennedy writes that they are at their best in late fall.
The jicama (pronounced HEE-kah-mah) is a large root vegetable roughly the shape of a beet or turnip but with a crisp, sweet texture more reminiscent of a water chestnut. Its tan and somewhat fibrous exterior is peeled away to reveal the creamy-white flesh within. Though I hear they can be cooked as well, we generally serve them raw, julienned and tossed as a slaw with ingredients such as lime juice, cilantro, and pomegranate seeds. They come in a wide range of sizes. The one shown above weighed about a pound and a half (producing about 6 cups of julienned flesh), though I’ve purchased jicama that were as small as 6-8 oz. They can grow much, much larger (wikipedia claims 20kg/44lbs), but the smaller specimens are sweeter and more tender. Opinions vary on how best to store your jicama. I’ve found that leaving the peel on and storing them in a cool, dark place (much like you would store potatoes) till I’m ready to use them works just fine.