Stew the chopped onions in vinegar. Then pour in the unpeeled rhubarb cut into slices about 1/2 cm thick and all the remaining ingredients and bubble for 6 min. Fill into glasses, close and keep cooled.
Try finely sliced cooked ham on cooked and baked celery slices with it.
Tip: Always use an aromatic ham, it will add a wonderful touch to your dish!