Loyal reader M. and I ventured over to 15th and K recently to check out the world famous Burrito Cart. Verdict: pretty good. Definitely the best in our relatively burrito-deprived work neighborhood. (Second best being the Burrito Brothers in the food court of International Square, IMO.)
They stick to the basics here -- just beans (pinto, black or "black and tan"), a few flavors of tortillas, and the possible additions of rice, cheese, sour cream, and guacamole. Plus, like a million kinds of hot sauce. But really tasty. The beans were excellent, with a hint of cinnamon. And M. had the mango salsa, which he liked.
It was quite an operation. We got there just in time, because about 10 people lined up behind us while we were waiting. So prompt and decisive ordering was at a premium, which was a bit stressful. Also, you make your own change, which was made difficult by the fact that we didn't know how much anything cost.
The only drawbacks: We both ordered a little conservatively -- I asked for a "5" in terms of spiciness, and M got a "7" -- and we'd both go hotter next time. And burritos are not the ideal food to eat on a park bench. Other than that: highly recommended!