Gwynnett St. in Williamsburg Brooklyn THE one-story exterior facing Graham Avenue, in East Williamsburg, Brooklyn, was totally unornamented except for a cryptic pair of stone lions up on the cornice. The dining room was plain, too, harking back to the days when nothing said hip, contemporary and urban better than exposed brick. At the end of the bar was what looked like, and under the previous ownership was, a pizza oven. Now it was baking miniature loaves of whiskey bread. They cost $5, tasted sweet and old-fashioned, and brought me back to those sprawling family restaurants that serve turkey with hot gravy on Sunday afternoons. Until the first course, in fact, nothing about Gwynnett St. hinted at what the kitchen had in store for me. But now servers had silently flanked the table. The one on my left decanted creamy salsify soup into a bowl dotted with crunchy bits of sweet-and-sour water chestnuts and a dab of shiso oil and fresh shiso leaves. I'd never imagined that the minty, lemony herb would have so much to say to the rich, oystery flavor of salsify. Or that a soup that brought them together could be so seductive. To my right, somebody had just been given a mound of roasted maitakes draped in a glistening sheet of lardo. It looked like a pine cone after an ice storm. Poked, the mushroom fell apart into mouth-size bites ready to be swabbed in a gentle cream of onions and rosemary. Across the table, two planks of brown-butter-roasted carrot lay alongside two strips of slow-cooked lamb breast, crisp and richly melting. . The sauce was thick, saffron-colored yogurt that tasted of carrots. . Crumbled rye toast with caraway and brown butter lent an Eastern European flavor. And what was that grassy herb? A sprig of carrot tops? Like almost everything at Gwynnett St., that lamb breast is not as simple as it looks, but its complications work together to build a marvelous sense of harmony. The restaurant opened in November with Justin Hilbert in charge of the kitchen. Mr. Hilbert worked at Wylie Dufresne's idea factory, WD-50, after going abroad for a while to peer into the abyss at Mugaritz, the Basque restaurant where diners are routinely antagonized with potatoes inside baked clay, and the like. Back in New York, Mr. Hilbert isn't antagonizing anybody. He follows Mr. Dufresne's decentralized approach to cuisine - using modern craftsmanship to build a dish out of separate components that are crunchy, chewy, smooth and so forth - but without Mr. Dufresne's fondness for tough-love flavors like black licorice and chicory. Mr. Hilbert is after quieter effects, teasing multiple forms and textures out of a few compatible flavors. His smart-wallflower style is best displayed in the Amish chicken with potatoes, beets, rutabagas and hay ash. What the what? All the cool kids are cooking with ashes these days. You didn't know that? This chicken is soaked in a brine made with ash, then cooked with more ash rubbed into its flesh. The surprise is that it does not taste anything like a chimney. In fact, the chicken has a sweet and salty flavor, like a mild ham, with a dusting of something that tastes a bit like smoked mushrooms. Our table ordered it in a gambling spirit. It turned out to be the dish we all fought over, even more than we did over the long strips of duck breast that looked like flank steak and tasted incredible. Mr. Hilbert's style of cuisine is not yet common in this pocket of Williamsburg. In fact, cooking this sophisticated would be a find anywhere in New York. And while it is a restaurant in Brooklyn, Gwynnett St. is not really a Brooklyn restaurant. There are no butchers" tools hanging from reclaimed barn doors. Under the eye of Carl McCoy, the proprietor, the dining room staff is calmly professional, utterly free of pretense and attitude. Nobody is the least bit likely to pull up a chair and offer to show you pictures of the sauerkraut the chef is currently fermenting inside a pair of Red Wing boots. Looking around the attractive but plain-spoken dining room, you get the sense that the pizza oven was left in place largely because tearing it out would have cost too much. The budget seems to have driven many of the other design decisions, down to the single restroom decorated with vintage car-repair manuals and an 1869 map of the neighborhood. It shows a thoroughfare called Gwinnett Street, later renamed Lorimer Street.