A dimly lit chandelier and some table candles illuminate this intimate Washington Avenue venue; a large mirror and family-style photos of the owners serve as décor. Twenty-four seats surrounding linen-draped tables and a petite cooking station occupy the rest of the teeny arena (with about two dozen more seats outdoors). The palate gets teased from the start via slices of baguette served with soft white truffle-perfumed butter and a plate of pickled vegetables. Chefs Horacio Rivadero (executive) and Christian Alvarez (de cuisine) show a consistent knack for adding sharp flavors that puncture the routine nature of dishes. To wit: Celery sprouts, a small dice of green apple, and a splash of vanilla heighten a vegetarian butternut squash soup; a salad of arugula and duck confit bores through the stale, old French standard via grilled apricots and a kumquat vinaigrette; and grilled nubs of calamari are spicily spiked with chili, citrus, cilantro, and kalamata olive purée. Entrées, too, are scintillating, such as halibut that whirls with a carousel of Brussels sprouts, parsnip purée, and minced trumpet mushrooms. A hunk of slow-braised pork shoulder is no less impressive with sharp multicolored grain mustard, a meltingly luscious white-bean purée, and pickled radish slices. A small "Patagonia" dessert brings fresh, soft swirls of browned Italian meringue encasing layers of pistachio cake and dulce de leche ice cream; blackberries, blueberries, and dabs of passion fruit sauce dot the plate. The Dining Room is a simple spot and a simply wonderful place for dinner.