Potato and sauerkraut gratin

Method

1. Heat the butter or fat in a frying pan and, when it is fizzing, add the bacon. Fry for a few minutes, then add the onions, spices and bay leaf. Cover and sweat for 7-8 minutes, stirring halfway, until the onions are soft. Fold in the sauerkraut.
2. Meanwhile, cut the potatoes into 5mm thick slices. Blanch in salted, boiling water for about 5 minutes, then drain well and set aside.
3. Preheat the oven to 190°C/fan170°C/gas 5. Add the wine or cider to the onion mixture and bubble for 2-3 minutes. Add the stock and simmer rapidly for 6-8 minutes, stirring occasionally, until three-quarters of the liquid has evaporated. Take off the heat and stir in the crème fraîche.
4. Fill a deep 2-litre ovenproof dish with alternate layers of potatoes and the onion mixture, pouring over any juices left from the onion mixture. Cover with foil and bake for about 50 minutes or until very tender.