39 Downing St.
Once upon a time, late-night dining was a sad, dark affair, limited to iron bellies, yahoos, and people too drunk to notice whether their warmed-over strip steak was done medium or rare. Not anymore. At Mas (farmhouse), in the West Village, it's possible to stumble into the diminutive, beautifully appointed dining room at 3 a.m. and find yourself face-to-face with a little fleet of Kumamoto oysters (decked with paddlefish caviar and a splash of rose champagne), or braised beef short ribs (with sauce bordelaise), or a perfectly articulated potato tart, strewn with bits of applewood-smoked bacon and Gruyère cheese. There are artisanal cheeses, of course, and a full complement of raw-bar goodies, and if you're weary of the rotgut you've been drinking all night, do what we do and wash it all down with a glass or two of the house cocktail, made with orange bitters, pomegranates, and premier cru Pierre Gimonnet champagne.