The MFK Fisher quote at the top of the menu (which I can't remember, haha) means two things: 1) shoot, wrong place to eat alone, and 2) they probably know their stuff. Re 1): there was some confusion about whether the person next to me was with me, and a lot of commentary about my eating alone here and why I was doing so, which was a bit awkward.
Re 2): I had heard a lot about Agave y Aguacate and actually walked four miles during a storm for dinner there. I ended up ordering the poblano and the lengua (beef tongue stew). The poblano was a generous portion for $9 -- stuffed to the gills with a lovely guac, pickled onions and carrots on top, and a pineapple sauce. While the latter two elements cut the creamy fattiness of the guac, it was a bit strong/acidic for me. I really enjoyed the lengua -- the sesame seeds on top were a nice touch, though I wish more bread was included.
Service was quite attentive, although note that there's no actual seating in front of the bar -- the smaller tables on the lower level are on the opposite side of the wall.