One random recommendation: my wife and I were once wandering around DuPont Circle, and lots of places were overflowing with people and had long lines. We ended up back near the Metro station and stumbled into a trendy-looking place that we thought, from the architecture, was some kind of fusion-funky restaurant. Instead, Levante's turned out to be one of the best Turkish restaurants I'd ever eaten at. Bring a healthy appetite and order the "adana yogurt". This starts with kebabs of spicy, ground lamb. That's placed on a bed of bread chunks (not quite as crunchy as croutons, but same basic idea), covered in a yogurt sauce, and also served with grilled tomato and some other veggies. It's very filling and very, very tasty.