Let the canned sauerkraut boil in a saucepan with water until soft (with sauerkraut there must still be a little liquid in the saucepan).
In the meantime, dice the fat bacon and leave it in a pan. Peel and dice the onion and add to the bacon. Stir until the onion cubes are translucent.
Add salt, pepper, nutmeg and a few teaspoons of sugar to the sauerkraut, depending on your taste.
Add the flour to the fat in the pan and let it burn in. Then add the whole thing to the sauerkraut. It has to be nice and creamy. Finally, season again as required and serve.