From The Food Encyclopedia by Jacques Rolland and Carol Sherman
Also bok choi, celery mustard, Chinese chard, Chinese white cabbage, choy sum, pak choi, pak choy. A mild leafy vegetable with crunchy stalks and tender, dark green leaves, bok choy originated in China or East Asia. Its name translates literally as "white vegetable" because of its white bulbous stalk. There are at least 33 different varieties of bok choy, most of them totally unknown in the U.S. Although consumed for thousands of years in China, it has only been known in Europe since the 18th century. Chinese workers who participated in the Gold Rush at the end of the 19th century were the first to introduce bok choy to the U.S. It can be eaten raw, cooked, fried or marinated, but overcooking will wilt the leaves and ruin this beautiful vegetable.
