Del Campo, web site, 777 Eye Street NW, Washington, DC, 202-289-7377 (Metro Trip Planner – opens in new window) [Google | WaPo | Washingtonian | ModernLuxury DC | Don Rockwell | Yelp]
Update August 2019: CLOSED – see Poca Madre
This place is pretty awesome. Get the rib-eye (easily arranged for sharing, and one of the best in DC), the empanadas, the chorizo, the sides, and don’t forget the superb bread they start the meal with. Real gaucho food, and the restaurant has a nice ambience to boot. The sandwiches are supposed to be good, but I have not tried them.
Not cheap, but a winner all around and it fills a gap in the DC dining scene.