Known for his virtuosic seasonal French cooking, David Bouley experiments in nouveau Austrian cuisine in a jewel box of a restaurant that evokes turn-of-the-20th-century Vienna. The elegant bar is alight with shimmering mosaic swirls, and the diminutive dining room is lined with sparkling Klimt reproductions. While signatures such as ravioli of Corinthian "Schlutzkrapfen" cheese with smoked hen-of-the-woods mushrooms still grace the menu, these days executive chef, and actual Austrian, Mario Lohninger is making his own headlines with dishes such as an intensely flavored oxtail consommé with bone marrow dumpling, and seared river sturgeon with crescent potato, Belvedere vodka, and osetra caviar. The wine list is notable for hard-to-find Austrian and German labels. Reservations essential. Jacket required. Subway: 1, 2, 3, 9, A, C to Chambers St.