Categories: Sauces 
      Yield: 1 servings 
  
    3/4 c  Watercress,packed,chopped 
    3/4 c  Unflavored nonfat yogurt 
    3/4 c  Mayonnaise 
      1 tb Lemon juice 
    1/2 ts Dried tarragon leaves 
      1    Garlic clove 
      2 ts Fish sauce or anchovy paste 
  
  In a blender or food processor, combine watercress, yogurt, 
  mayonnaise, lemon juice, tarragon, and garlic; whirl until smooth. 
  Add fish sauce to taste; whirl to blend. (If sauce is made ahead, 
  cover and chill up to a day.) Makes about 1 1/2 cups.