Most of the Chinese soups we find in the West are the clear, thin sort called tong in Chinese. Here is a different soup altogether. Known as keng, or chowder in English, it is a thick, rich, hearty brew that in ancient north China comprised the main part of a meal. What Confucius ate six nights of the week was probably a gung.
Plunge fresh tomatoes briefly in boiling water just until the skin splits, remove with a Chinese mesh spoon or slotted spoon, and let cool. Peel and core, retaining the juices. Cut fresh or canned tomatoes into quarters and chop coarsely, in the food processor using on-off turns, or by hand. Retain the liquids.
Clean the mushrooms by bobbing them and rubbing them gently in a bowl of cold water. Cut off only the ragged or brown base of the stems, then put the mushrooms on their sides and cut into thin umbrella-shaped slices 1/16 inch thick.
String snow peas or sugar snap peas and cut on the diagonal into slivers a scant ¼ inch thin. Defrost frozen peas. Cut off the tips of string beans or longbeans, then cut on the diagonal into 1¼-inch lengths.
The cut vegetables may be sealed and refrigerated overnight. Seal the green vegetable in lightly misted plastic.
About 10–15 minutes before serving, assemble all the ingredients within easy reach of your stovetop, and put individual soup bowls in a low oven to warm.
Heat a heavy non-aluminum stockpot over medium-high heat until hot enough to evaporate a bead of water on contact. Add the oil, swirl to glaze the bottom of the pot, then heat until a bead of wine added to the pot “explodes” in a sizzle. Add the wine, allow only 1 second for it to explode in a fragrant hiss, then immediately add the stock to capture the wine essence. Bring the stock to a boil, then add the tomatoes, mushrooms, and com. Cook over moderate heat, stirring constantly, until the mixture returns to a boil. Do not increase the heat or cease stirring, lest the soup scorch. Reduce the heat to maintain a steady simmer, then add the green vegetable. Simmer about 2–3 minutes for snow peas or peas, 4 minutes for beans, stirring constantly until the vegetable is cooked but quite crisp. It will continue to cook while you finish and serve the soup.
Taste the soup, and add salt and sugar as needed. Store-bought tomatoes, especially, will require sugar to restore the natural sweetness bred out of them. Do not hesitate to add it. Otherwise, the soup will lack sparkle and taste flat.
Reduce the heat to low. Stir the cornstarch mixture to recombine, then add it to the pot in a steady stream, stirring slowly for about 2 minutes until the soup turns glossy and thick. Turn off the heat. With a fork or chopsticks beat the egg white with quick, light strokes just to break the gel. It will froth a bit, but do not beat to a foam. Holding it about 6 inches above the surface of the soup, add the egg white in a very thin, steady stream. Stir gently once midway, and again when finished to bring the lacy threads to the surface.
Serve immediately, garnishing each bowl with a sprinkling of ham. Or, cover the pot and serve 1–4 hours later, when the vegetables are no longer crisp but the soup is even deeper in flavor.
Leftovers keep nicely 4–5 days, refrigerated, or may be frozen. Reheat in a heavy pot over medium heat, stirring frequently.
© 1982 Barbara Tropp estate. All rights reserved.