Sauerkraut is on this site for a specific reason: it is one of the few shelf-stable things in the cupboard carrying useful vitamin C. It is also, cooked like this, extremely good, which is the more persuasive argument.
- Oil, dried onion two minutes until it softens and colours a little.
- Drain the sauerkraut but do not rinse it. Rinsing is what people do when they are frightened of it, and it washes out the point. In, with the stock cube crumbled over and 150 ml water.
- Lid on, fifteen minutes at a low simmer. It goes from sharp to round.
- Drained potatoes in, crushed slightly against the pan. Frankfurters on top, sliced into lengths. Lid back on for five minutes to heat through.
- Mustard stirred through at the table, not in the pan.
The sourness is doing the same job acid does everywhere else on this site: it cuts fat and stops a plate of beige food tasting like one thing.
Serves 3.