It’s 3 a.m. on a December’s night in 1997, and I’m sitting in Gammeeok, a cozy restaurant on 32nd Street, Koreatown in New York City. Despite the hour, the restaurant is buzzing, full of late-night revelers wanting a bit of sustenance after a long night of drinking. It’s bitterly cold outside, and I’m tucked into a comfy corner table with some friends. The rustic, blond wooden décor gives the restaurant the homely feel of a hanok, a traditional Korean house, and a savory, beefy aroma fills the air. In the back, an open Korean-style hearth, called a buttumak, boasts two gigantic black cast iron pots, called gamasot, settled over roaring fires. An elderly man stands next to the cauldrons with a long, dark wooden paddle and slowly stirs the silky, milky-white liquid inside—the magical broth that everyone has come for. Seolleongtang, this nourishing, long-boiled ox bone soup, is the signature …