1. Steam the burdock on a steamer rack over water 40 minutes, or until tender enough to pierce with a fork, or pressure cook it 15 minutes.
2. Drain the burdock and put into jar.
3. Place a fork in the jar to prevent it from shattering.
4. Meanwhile, mix the vinegar and the water, and bring to a boil.
5. Pour this over the burdock and stir in the remaining ingredients.
6. Remove the fork, cover, and refrigerate at least 12 hours before serving. This recipe lasts for weeks refrigerated.