Szechwan Preserved Vegetable

This is a delightfully crunchy pickled vegetable, with a crisp and refreshing salty aftertaste, something like a good kosher pickle. It is regularly canned under the name Szechuen Preserved Vegetable or Preserved Szechwan Mustard, and may sometimes be found in Chinese markets sold loose in 2-foot high, brown-glazed crocks. The appearance of the vegetable—which is neither mustard nor kohlrabi as is often said, but rather the knobby root end of a leafy green cabbage—is somewhat forbidding. It is covered by a thick, red paste that smells as bad as it looks.