Put the brisket into a saucepan with a volume of 5 liters, pour cold water and cook under a medium heat. Skim off the foam, slack the fire, add 1 tsp. salt and bay leaf and cook for 1.5 hours. Take out the brisket, remove the meat from the bones, cut into small pieces and put back in the broth (no need for bones). Cut lard and onions into small cubes. Thick grate carrots and beets. Warm up the frying pan and put half the lard in 3 minutes. Add onions. Fry stirring for 5-7 minutes. Add the carrots, stir and fry for 5 minutes. Fry the remaining lard in another pan under a low heat, add the beets, sugar and vinegar and fry for 10 minutes, stirring. Add tomato paste to the beet and fry for another 2 minutes. Peel potatoes and cut into cubes. Chop the cabbage thin. Bring the broth to the boil, add the potatoes and cook on low heat for 3 minutes. Put cabbage and cook for another 5 minutes. Add carrots with onions and beets. Simmer under the lid for about 10 minutes. Peel the garlic and chop with parsley as small as possible, add to the borscht, close the lid, remove from fire and let the borscht draw for about 10 minutes. Serve with sour cream.