Manna
Manna, 8640 Flower Avenue, Takoma Park, MD, 301-589-9390, usually open (Metro Trip Planner - opens in new window) [Yelp]
Go here for mofongos (see under Puerto Rico for an explanation), fried pork and chicken, cuban sandwiches, and cow feet soup. I haven't been here yet, but I have heard good reviews.