Cho Cu Saigon
Cho Cu Saigon, 6763-6D Wilson Blvd., Falls Church, VA, 703-538-2168, inside Eden Center (Metro Trip Planner - opens in new window) [Washingtonian | City Paper | Yelp]
Get the roast pork there. You might call this Cantonese but it is a Vietnamese vision of Cantonese food. Duck and seafood as well, recommended.
Update September, 2006: An unknown and much underrated Cantonese restaurant. Good congee. Also get the salted and baked chicken. Fully authentic, try the noodles with ginger and scallion, I think this place is quite good and I haven’t even yet discovered their best dishes.
Update March 9, 2006: Today I had a great meal at the Cantonese place inside Eden Center... the casserole with minced chicken and salted fish was superb.