This used to be the salad for the ladies who lunch. When it was originally served at the Waldorf Astoria, it was just apples, celery, and mayonnaise atop a bed of lettuces. Walnuts were added later. I’ve added the chicken, although leftover cooked turkey works well, too. It’s a recipe that follows my theory–good salad, great sandwich filling. It can be served on white bread, white toast, or walnut bread, if you can find an acceptable commercial loaf.