Remove the outer leaves from the cabbage and cut the stalk into strips. Fry the onion in oil, add the mince and brown, season with salt and pepper. Then add the cabbage, put the lid on and let it simmer for 20 minutes. Then add the tomatoes and simmer for another 15 minutes. Finally add the cream, sour cream or creme fraiche. Simmer for another 5 minutes and season to taste.