In large pot with lid, combine chicken broth, bouillon cubes, carrots and celery. Cook, covered, over low heat for about 10 minutes.

Add pickles and cooked chicken and continue cooking for another 15 minutes.

In a small bowl, beat milk and flour until smooth. Stir in a small amount of hot soup into the flour mixture. Mix until smooth and pour into soup pot, stirring until well combined. Bring soup to a boil, stirring frequently, until soup is slightly thickened. Remove from heat.

In a small bowl, beat egg with sour cream until smooth. Pour a small amount of hot soup into sour cream mixture and mix thoroughly. Return sour cream mixture to soup pot and stir until smooth. Keep sour cream warm but do not boil after this point or egg/sour cream will curdle.

Add salt and pepper to taste. Serve over rice.

Garnish with parsley and dill, if desired.