Finely chopped onion sweated in olive oil and butter.
Mix fnely shredded red cabbage into sweaty onion.
Add finely chopped apple. Splash all with wine vinegar and a cup of water and ground black pepper. Cook on low heat for 2 - 2.5 hours, add a handful of raisins or sultanas for last hour.
Stir from time to time to avoid burning, add vinegar or a little brown sugar + black pepper to adjust sweet-sour taste.
Great with pork.