In a large frying pan, heat half a tablespoon of olive oil and cook the onion for 5 minutes until soft. Transfer the onion to a large bowl, add the mince, apple sauce, sage and breadcrumbs. Season with freshly ground black pepper and mix together until well combined.
Shape the mince into 12 balls. Heat the remaining oil in the frying pan and fry the meatballs for 10 minutes, turning, until cooked through with no pink remaining. Remove from the pan, set aside and keep warm.
Stir-fry the cabbage for 2 minutes in the frying pan.
Make the sauce: heat the soured cream in a small pan and stir through the cornflour mixture. Slowly add the beef stock and simmer for 5 minutes until thickened. Meanwhile, heat the mash to pack instructions.
Serve the mash with the meatballs, cabbage and cranberry sauce, then pour over the sauce.