Back when I haunted the area, there were a lot of great restaurants on King St. in Old Town Alexandria. My very favorite was the now defunct Scotland Yard...the atmosphere, food, portions, etc. made for a perfectly satisfying experience, and the way they decorated for Christmas was right out of the 19th Century.
I loved the Scotland Yard in Alexandria. The Scottish proprietor with his heavy accent always offered to seat us in a “beeph” under our hanging tartan. (That’s booth in America.) His wife appeared to be 30-years his junior and do all the work! Sad to see it go.
Another favorite years ago was the Bamiyan in Georgetown. Oh, what they did with eggplant and spices! They called one day to cancel our reservations for that night because the cook was in jail. Place closed up shortly after.
Tabard Inn near Dupont Circle is my favorite DC restaurant that still exists. Amazing food in a beautiful old building with walled courtyard.