Chicken soup may or may not be a cure-all for physical and psychic ills, but if you add a few matzo balls it definitely becomes a deli classic. This recipe, from Gillie Feuer of Long Island, New York, was a tightly held secret, until we pried it loose. The key? Lots of veggies, and her light and floaty dumplings: "They're very well behaved," she told us. "They plump up just like little dolls." The trick? "Margarine." But, she warned, "I'm not perfect. You can see my fingerprints on them." It might just be the fingerprints that make them so good.