Kaz Sushi Bistro, web site, 1915 Eye Street NW, Washington, DC, near 20th, 202-530-5500 (Metro Trip Planner – opens in new window) [Economist | Washingtonian | The Hill | WaPo | City Paper | Don Rockwell | openlist | Yelp | Gayot]
A mix of Japanese and fusion, both the beef and the sushi can be very good. It has much more variety than your typical Japanese place, you won’t get bored here even after a few visits. Washington needs more of this kind of place. Get the kobe beef. Lately, however, I’ve seen some signs of decline. It remains well above average, but beware.
Update April 2012: See “Food’s Biggest Scam: The Great Kobe Beef Lie,” by Larry Olmsted, Forbes, April 12, 2012