The cashew nut grows at the bottom of an edible, pear-like fruit (cashew apple). Cashew nuts have a sweet, buttery flavor. You never see cashews for sale in the shell because between the outer and inner shells covering the nut is an extremely caustic oil. The outer shell must be roasted or burned off with the oil. The kernels are then boiled or roasted again, and a second shell is removed. Cashews are native to the Amazon region, and were introduced to India by the Portuguese in the 16th century. Today, India and East Africa are the world's largest producers.