Sauerkraut

Plain fermented cabbage. The only thing that matters is the salt: 2% of the cabbage's weight, so weigh the cabbage after trimming and scale the salt to it.

Recipe

Peel off and discard the limp outer leaves, then set aside one clean whole leaf. Quarter the cabbage, cut out the core, and shred thinly. Weigh it and work out 2% of that weight in salt.

Toss the cabbage with the salt in a large bowl. Squeeze and knead it with your hands until it wilts and a puddle of brine collects in the bottom, 5–10 minutes. Mix in the caraway.

Pack into a 1-quart jar a handful at a time, pressing each addition down hard with a fist or spoon until brine rises over it. It will seem like too much cabbage; keep pressing. Pour in any brine left in the bowl. Lay the reserved leaf on top and weigh it down (a small jar of water works) so everything stays under the brine, leaving about 1 inch of headspace. Cover loosely so gas can escape.

Leave at cool room temperature (65-72°F), out of direct sun, with a plate underneath. Press down daily to keep the cabbage submerged and skim any scum. Start tasting after 5 days; it is done when it is as sour as you like, usually 1–3 weeks. Cap tightly and refrigerate; it keeps for months.