Watercress Sauce

Ingredients

3/4 c watercress
3/4 c nonfat yogurt
3/4 c mayonnaise
1 tb lemon juice
1/2 ts tarragon leaves
1 garlic clove
2 ts fish sauce

Instructions

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.