From the Fannie Farmer Cookbook
1 cup chicken or vegetable broth
1 1/2 –inch piece ginger root, quartered
2 pounds bok choy
3-4 Tablespoons rice wine vinegar
A few drops hot pepper oil
Salt, to taste
Pour broth into a large sauté pan and add the ginger. Cut the bok choy into halves or quarters and add to the sauté pan with the salt. Cover and simmer on low heat for about 10-12 minutes. Test for doneness by piercing the bulb end with a knife tip. When done, discard the ginger root and place the bok choy on a serving dish. Sprinkle with the vinegar (and hot pepper oil if desired).