Peel the carrot and onion and cut into strips. Fry both in oil briefly. Cut cabbage, celery and parsley root into strips.
Peel potatoes and cut into bars. Cut gherkins lengthwise into slices and then cut them diagonally into strips.
Bring soup to a boil and add cabbage, potatoes and root vegetables. Simmer  5 minutes and then add the roasted carrots and onion strips.
Season with bay leaf, salt and pepper and cook until tender.
Cut cooked beef into pieces and add to the pot. Just before serving add the gherkins.
Serve garnished with sour cream and chopped parsley.