Tarragon Dressing

3/4 C plain nonfat yogurt
1/2 C tarragon vinegar
1 T olive oil
2 T scallions, finely minced
1/2 tsp tarragon
Pepper to taste

Put all ingredients in a covered container and shake until blended. Chill for several hours and shake thoroughly before serving. Thin with a little skim milk if desired. Makes 1-1/2 C.