Let dressing sit overnight to meld flavors.

Ingredients

　　1/2 cup mayonnaise

　　1/2 cup sour cream

　　2 tablespoons buttermilk

　　1 tablespoon white-wine vinegar

　　1 teaspoon Worcestershire sauce

　　1 bunch chives, coarsely chopped (1/2 cup)

　　2 green onions, coarsely chopped

　　2 tablespoons chopped fresh cilantro

　　2 tablespoons chopped fresh flat-leaf parsley

　　1 teaspoon sugar

　　1 teaspoon coarse salt

　　1/2 teaspoon freshly ground black pepper

　　Pinch of cayenne pepper (optional)

　　Combine all the ingredients in a blender or food processor; process until smooth. Refrigerate in an airtight container up to 3 days.

　　Reprinted with permission from The Martha Stewart Living Cookbook: The New Classics by Martha Stewart Living Magazine, copyright © 2007. Published by Clarkson Potter, a division of The Crown Publishing Group.Buy the full book from Amazon.