In a large, heavy metal pot pour in the oil or lard and fry the onion gently until golden.
Throw in the cabbage, sugar, vinegar, salt and 1 cup of water and mix until coated.
Cover with the lid and allow to simmer, stirring occasionally for 1 hour.
Add more water if the mixture appears too dry.
Remove the lid and stir in the caraway seeds and cook for another 30 minutes.
The cabbage should taste more sweet than sour.
Spoon generous amounts to the side of the duck and dumplings.
If you are in a hurry you can cook it for 30 minutes only but it is best if you allow it to cook very slowly for 2 hours.