French Truffles are the fruiting body of an underground mushroom; There are hundreds of species of truffles, but the most fruiting truffles are very expensive as a food. One of the things that has made truffles so highly expensive is the fact that truffles are very difficult to cultivate. The culinary world increase their usage of truffles as they became more widely known and more available. Truffles are still very much a specialty item and very expensive one at that