Steve Siegel has been touting this place for a few weeks. It's run by the folks who once had the taco truck at Route 50 and Pershing. I've now been twice, and all I need say is that all Chowhounds should get themselves over there right away! Today I ordered the cabrito, pork and chicken tacos, the torta, and two pupusas. (Twelve dollars -- enough for three meals.) The pupusas are made to order, and are delicious. The tacos are wonderful, too, each one a bit different than than the others. (So far, I think the pork and lengua are my favorites. Haven't tried chorizo yet.) And the torta was, I think, the best steak sandwich I've had in the DC area.
Don't get me wrong: This place isn't revelatory, in the way that La Super-Rica in Santa Barbara is. Nevertheless, it's bowling me over, perhaps because it's so hard to find this sort of thing done so consistently well in DC.
I'd be curious to know whether transplanted Californians such as Zora M. think that it's as good as some of the better places in LA and SF.