Mango-jicama salsa is fantastic. It goes great as a topping for grilled fish, too. I can’t find the recipe that I usually use, but this one looks close:
http://www.bhg.com/recipe/appetizers-snacks/mango-kiwi-salsa-with-jicama-chips/
http://www.epicurious.com/recipes/food/views/GRILLED-FISH-TOSTADAS-WITH-PINEAPPLE-JICAMA-SALSA-232552
From Wikipedia:
ícama (Spanish: hee-kah-mah, from Nahuatl xicamatl hee-kah-mahtl), also Mexican Potato and Mexican Turnip, is the name of a native Mexican and Central American vine, although the name most commonly refers to the plant’s edible tuberous root. Jicama is one species in the genus Pachyrhizus that is commonly called yam bean, although the “yam bean” sometimes is another name for Jicama. The other, major species of yam beans are indigenous to other parts of the Americas.
The jicama vine can reach a height of 4–5 metres given suitable support. Its root can attain lengths of up to 2 m and weigh up to 20 kilograms. The root’s exterior is yellow and papery, while its inside is creamy white with a crisp texture that resembles raw potato or pear. The flavour is sweet and starchy, reminiscent of some apples, and it is usually eaten raw, sometimes with salt, lemon, or lime juice and powdered chili. It is also cooked in soups and stir-fried dishes. Cultivation of jícama has recently spread from the Americas to China and Southeast Asia where notable uses of raw jícama include popiah and salads such as yusheng and rojak.
In contrast to the root, the remainder of the jícama plant is very poisonous; the seeds contain the toxin rotenone, which is used to poison insects and fish.
Jícama is high in carbohydrates in the form of dietary fibre. It is composed of 86–90% water; it contains only trace amounts of protein and lipids. Its sweet flavour comes from the oligofructose inulin (also called fructo-oligosaccharide).
Jicama should be stored dry, between 12°C and 16°C (53°F and 60°F); colder temperatures will damage the root. A fresh root stored at an appropriate temperature will keep for a month or two.