Knead the red cabbage with salt and sugar. Mix in the orange juice, cranberries and balsamic vinegar and marinate everything in a well-sealed container for 1 day.
Heat the olive oil in a large saucepan and fry the shallots in it. Add red cabbage and apples, pour in red wine, orange juice and vegetable stock and bring to the boil. Cover and simmer over a medium heat for 30 minutes, then puree with a blender and season to taste.