For the pickled red cabbage, cut the red cabbage in strips and put it in a bowl. In the same bowl, add the vinegar, the water, the brown sugar and the salt. Mix it all together and let it marinate for at least one night.
Melt some butter in the pan and fry the onion over medium heat for 30 minutes. The onion is ready when it gets golden brown and sweet.
Bake the sausages according to the instructions on the package.
Cut each bun open lengthwise and place two sausages between each bun. Finish with the pickled red cabbage, dried onions and a bit of parsley. You can finish it up adding some ketchup or mustard.