1. Combine beef and water in a large stockpot and bring to a boil over high heat. Skim and reduce heat to low. Add the whole onions and carrots and the bay leaf and season with salt and pepper to taste. Simmer partially covered until the meat is tender, about 1½ hours. Strain the stock, removing the meat. You should have 11 to 12 cups of stock. Cut the beef into 1½-inch chunks and reserve.
2. While the stock cooks, preheat the oven to 400 degrees Fahrenheit. Wrap the beets separately in aluminum foil and bake until the tip of a small knife slides in easily, about 45 minutes. Unwrap the beets, plunge them into a bowl of cold water, then slip off the skins. Grate the beets on a four-sided box grater or shred in a food processor. Set aside. Strain the mushroom soaking liquid and save for another use. Chop the mushrooms.
3. In a large, heavy soup pot, cook the bacon over medium-low heat until crispy. Remove with a slotted spoon and reserve. To the bacon drippings, add the chopped onion, mushrooms, diced carrot, and green pepper, and cook until softened, about 7 minutes, adding a little butter if the pot looks dry. Add the remaining butter and cabbage, and cook, stirring, for another 5 minutes. Add the paprika and stir for a few seconds. Add the stock, potatoes, tomatoes with their liquid, apple, and the reserved beef, and bring to a gentle boil. Skim off any froth, season with salt to taste, cover, and simmer over low heat until potatoes are almost tender, about 15 minutes. Stir in half of the reserved beets and the beans, and add a little water if the soup looks too thick. Continue cooking over medium-low heat until all the vegetables are soft and the flavors have melded, about 25 minutes more. (The borshch can be prepared a day ahead up to this point. Reheat it slowly, thinning it out with a little water if it thickens too much on standing.)
4. Before serving, use a mortar and pestle and pound the garlic and parsley with 1 teaspoon of ground black pepper to a coarse paste. Add to the simmering soup along with the reserved bacon, the remaining beets, vinegar and sugar. Adjust the seasoning and simmer for another 5 minutes. Let the borshch stand for 10 minutes. To serve, ladle the soup into serving bowls, add a small dollop of sour cream to each portion, and sprinkle with dill and scallions. Invite the guests to mix the sour cream well into their soup.
Reprinted from the book MASTERING THE ART OF SOVIET COOKING by Anya von Bremzen. Copyright © 2013 by Anya von Bremzen. Published in the United States by Crown Publishers, an imprint of the Crown Publishing Group, a division of Random House LLC, a Penguin Random House Company, New York.