Having lived in DC for many years and working in the food consulting business, I'd say try the ethnic restaurants. This city abounds in Vietnamese, Thai, Ethiopian, Latin American, Middle Eastern and more. Try the Eden Center in Arlington for Vietnamese and groceries, Masala Art for Indian, go out to Wheaton and walk around the Triangle Lane area. You'll think you landed in the United Nations. Try Annandale for Korean. Flip through the Washington Post dining section for "bests." The expense account restaurants are obvious and well known.