Serves 6 to 8

The peak season for this substantial soup — a slight variation on my American-born grandmother’s Russian-born mother’s recipe — is mid-September through early October, those few weeks when summer tomatoes and autumn cabbage overlap. Elsie, on the other hand, made the soup all winter with canned tomatoes and we certainly never complained. If you DO use canned tomatoes, however, you may not need as much sugar as listed. Elsie always described the sweet-sour balance as “winey.” When you achieve it — by tasting and correcting, tasting and correcting — you’ll know it. In this version, lemon juice is used as the souring agent. My grandmother used “sour salt,” which is citric acid crystals. These are hard to find in some parts of the country — try your local pharmacy if you can’t find them in a food store (they are available mail order from the King Arthur baking catalog — but they do give a different, more authentic sour flavor than lemon juice. As Elsie, my colorful grandmother, once pointed out, “Lemons didn’t grow on trees in Russia.”

•  2 pounds flanken or short ribs
• 1/2 teaspoon salt
• 2  tablespoons vegetable oil
• 1 large Bermuda onion, cut in half and sliced
• 2-3 pounds ripe tomatoes (3 to 5 large), cored and cut into wedges (or 1 28- or 35-ounce can Italian plum tomatoes)
• 2  pounds cabbage, cored and shredded (about 10 cups)
• 2 quarts water
• 2 teaspoons salt
• 1/2 teaspoon freshly ground pepper
• 6 tablespoons sugar
• 1/4 cup freshly squeezed lemon juice or white wine vinegar or 1 teaspoon fine sour salt
• 2 1/2-3 pounds potatoes (4 to 6 large), boiled and peeled
• Snipped fresh dill (optional)

Sprinkle the meat on all sides with salt, then place it in a heavy, 8-quart pot. Place over medium-high heat and sear until browned on both sides, turning several times. Remove and set aside on a plate.

Immediately add the oil and the sliced onion. Saute for 5 minutes, until onions are wilted.

Add the tomato wedges and stir with the onions for 2 or 3 minutes, until the tomato juices start bubbling.

Add half the cabbage. Place the meat on the cabbage, then top with the remaining cabbage. Add water, salt, pepper and sugar. Cover and bring to a boil.

Lower heat and simmer, covered, very gently, for 2 to 2 1/2 hours, stirring occasionally, until the meat is so tender it practically falls apart when prodded with a fork.

Stir in the lemon juice and taste for seasoning, adjusting with additional salt, pepper, sugar or lemon juice, as desired.

Refrigerate the soup overnight, then skim off the hardened fat. Strip the meat into large pieces, discarding bones. Return the meat to the soup. Reheat the soup.

Serve piping hot in a deep bowl with a boiled potato on the side, or serve in a flat bowl with quarters or chunks of potato in the bowl with the soup. Sprinkle with dill only if you are one of those cooks who feel compelled to garnish; the mahogany colored soup is beautiful as is.

Advance Preparation: The soup is much better if made a day ahead and reheated. It also freezes very well. In either case, however, it’s flavor will require refreshening. Taste carefully for salt, pepper and lemon juice.