For the preparation of sauerkraut put the sauerkraut with plenty of water (about 3 finger widths over the sauerkraut in the pot fill with water) in a pot. Season with salt and caraway seeds and cook for about 1/2 hour.
In the meantime, chop 2 medium onions and fry in oil until golden brown. After about 1/2 hour of cooking the sauerkraut, mix in the roasted onion. Finally, mash 2-3 cubes of gravy and a cooked potato and mix into the cabbage as well.
Season to taste with caraway and salt.