Shchi (Cabbage Soup, Fresh or Soured)

Variations

• Kislye shchi (sour shchi): made with sauerkraut. The winter form, and the commonest one in Russia.
• Zelyonye shchi (green shchi): made with sorrel, spinach or nettle in spring, and served with half a boiled egg on top. The tip on green shchi below is about this one.
• Without meat: mushroom or fish versions are made for Lent. Dried mushroom soaking liquid gives the broth body that no meat is there to supply.
• In the oven: covered, at 150C for two hours, which is closer to what a Russian masonry stove did. Nothing boils, so the cabbage keeps its shape longer.
• A day later: better-the-next-day attaches to this soup more than to most (reviving leftovers).

Tips

• This soup's identity is its sourness, and where the sourness comes from is not fixed. There are three routes: the faint acid the cabbage itself gives up, the lactic acid of sauerkraut, or the sharp acid of a sour leaf like sorrel. All three are called shchi, and which one you use is decided by the season.
• Kimchi jjigae stands at the opposite end of the same axis. That page says the acid "has fermented and cannot be taken back out, so the vegetable's sugar is the only dial left." There the acid is the constant and the sugar is the dial; here the acid itself is the thing you choose. You can choose its strength too — rinse the sauerkraut once and the same dish comes out a step milder.
• The sharpest case is green shchi, and it is a shape the guide has no remedy for. Blanching explains why green disappears and then reduces the answer to three moves: "cook briefly, dilute the acid, and give the acid a way out." But with sorrel the acid is the vegetable. You cannot dilute it away — that is the flavour — and there is nowhere for it to escape to, because the liquid is the dish. Only the first move survives, so green shchi comes off the heat in two or three minutes, and the olive colour that remains is taken as the colour of the dish.
• The acid changes the order, and this is the practical part. Acid sets pectin so the vegetable stops softening — chili con carne states the rule, writing that "That guide's rule is that acid sets pectin firm," and it is why cassoulet and red red keep acid out of the pot altogether. That is the whole of step four: with sauerkraut the potatoes go in first. Reverse the order and they will still be crunchy an hour later.
• Fresh cabbage and sauerkraut are not the same ingredient. One is a vegetable, the other has been fermenting for a month and brings salt as well as acid. Bigos cooks it long and soft; here it gets twenty minutes and keeps both its bite and its sourness. That is also why the salt is judged at the end.
• The soured cream goes into the bowl, not the pot. Dairy and heat reduces dairy failure to three causes — too hot, acid present, added too early — and this pot has all three at once. In the bowl the broth has already dropped in temperature and the quantity is small, so it simply melts in.
• Garlic and dill after the heat is off. Both are volatile and twenty minutes of simmering leaves almost nothing of either. Ten minutes under a lid beats any amount of boiling.