In Boston's South End neighborhood, where my husband Ted and I moved more than thirty years ago, almost every corner used to boast a spa (Boston-speak for an all-purpose market), or a Middle Eastern grocery, or a bar. The bars have long since closed -- many replaced by the fine restaurants that now define the South End -- and, sadly, most of the Middle Eastern businesses have gone, too. The spas endure, and almost every one that offers prepared food sells a basic, uninspired, too-much-mayo chicken salad. My new chicken salad recipe with walnuts and celery features a pomegranate-harissa yogurt sauce that reminds me of the wonderful ingredients I used to buy at the local Middle Eastern markets. It's sweet and tangy, and as spicy as you want to make it, perfect in a sandwich or lettuce wrap. If I owned a spa in the neighborhood, I'd make this my signature chicken salad.