Also known as Chinese chard and Chinese white cabbage. Has fleshy white stems and leaf ribs and green flat leaves. It has a slightly mustardy taste. Separate the leaves, wash well and drain. The white stems can be sliced thinly and eaten raw. Look for firm stems and unblemished leaves. A smaller type is called baby bok choy or Shanghai bok choy. Keeps in refrigerator for one week. High in vitamins A and C.