Figure 21: Oca (Oxalis tuberosa). In the Andean highlands, it is second only to the potato, and remains a staple for Peruvian and Bolivian Indians living at high altitudes. Although the potato has gone forth and multiplied into a major food for mankind, oca has remained at home. New Zealand is about the only non-Andean nation that knows it. While growing up there, I enjoyed these red, wrinkled tubers which taste like potatoes that need no sour cream. The slight sourness makes them delectable. I predict these will be seen in supermarkets worldwide, perhaps quite soon.