By Kim Sunée Grand Central Publishing. 376 pages. $13.99 (paperback) If human nature perplexes you, be assured that Trail of Crumbs will leave you wondering even more about the nature of humans. Trail of Crumbs joins the ever-increasing ranks of a new food-writing genre — the food/culinary memoir. Recent members of this club include:  The … More TRAIL OF CRUMBS: Hunger, Love, and the Search for Home