In a blender, combine the egg, onions and garlic; process a few seconds til well mixed. With the machine still running, add the oil in a thin, steady stream; then add the butter milk and seasonings and process a few seconds more til well mixed, pushing the sides down once with a rubber spatula. Transfer mixture to a large bowl and add the cheese; mix with a metal whisk to bread up any large lumps, but leave the cheese somewhat lumpy. Refrigerate and sere cold on salad. Taste this for yourself, and add vinegar if desired. Donna/ North Nj
