Yams grown in New Zealand originate from the South American Andes where they are known as oca. Their waxy skins are shiny and colourful and is thin and soft and needs no peeling. The white to lemon-yellow flesh has a smooth, silky texture with a nutty taste, similar to beetroot. Earth gems have a crisp texture, which remains even when cooked. They can be boiled, steamed, microwaved or baked.