Ice Box Buttermilk Dressing
1/2 cup extra-virgin olive oil
1/2 cup reduced-fat mayonnaise
1/2 cup buttermilk
2 tablespoons grainy mustard, such as Moustarde de Meaux 2 tablespoons red wine vinegar
2 tablespoons chopped rinsed capers
2 tablespoons minced shallots
2 teaspoons chopped fresh oregano 1 teaspoon chopped fresh basil
1 teaspoon chopped fresh tarragon
1 teaspoon sugar
Salt and hot red pepper sauce, to taste
Place all the ingredients in a jar and shake well to blend. (The dressing can be prepared up to 1 week ahead, covered and refrigerated.) 
Makes 2 cups