Egg drop soup (don tong)

4 c  chicken broth
    1/2 ts Salt
    1/2 ts Sugar
      1    Egg
      1 ts Cornstarch
      1 tb Water
           * Water chestnuts (optional)
           * Green Onions (optional)
 
  PREPARATION: Add the salt and sugar to the broth.  In a separate bowl, beat
  the egg until frothy.  In a small cup, mix the cornstarch and water.
  
  COOKING: Bring the broth to a boil over medium heat in a soup pot.  Add the
  cornstarch mixture, and stir until slightly thickened.  Remove from stove.
  add egg very, very slowly, frop by drop, stirring constantly.
  
  OPTIONAL: If you wish add 2 minced water chestnuts, and/or one sliced green
  onion, including the white and green parts.