1/2 cup mayonnaise
1/2 cup sour cream
1/3 cup chopped fresh chives
1 chopped green onion
1 clove garlic, peeled
1 tablespoon cider vinegar
1 teaspoon chopped fresh tarragon
1 teaspoon white sugar
1 teaspoon Worcestershire sauce

Combine all ingredients in a food processor, blending until smooth. Season to taste with salt and pepper. Cover and refrigerate until serving. It will keep up to three days in the refrigerator.