Baltimore has a surprisingly wide selection of good, authentic Mexican food. As I described in this post, I very much enjoyed the food in Mexico during my work trip in December, and I was amazed at how different it is from much of what is served in the US, or in Norway for that matter. DC, for instance, does not have a great Mexican food scene (secondo me), either they are on the fancy end (Lauriol Plaza, Rosa Mexicano - which reminds me that I still haven't found out why it is called Rosa Mexicano with an o - if we are referring to the flower it should of course be Rosa Mexicana, but maybe it is named for a woman named Rosa Mexicano?) or they are more Salvadorean than Mexican, often with WAY too much cheese on everything.
In Baltimore, the area around Eastern Avenue and Broadway has many little Mexican places and so far I have two favorites. Las Palmas is a sit-down restaurant with excellent mole and delicious aguas naturales (fresh fruit juices mixed with ice and water). Tortilleria Sinaloa is a tiny place which serves both as a whole saler - they sell stacks and stacks of tortillas that they make on site ($ 1.70 for one kilo), as well as prepared meats for tacos (beef, beef tongue, carnitas) by the pound - and a take out place for tacos and pozoles. You can also eat in, the place probably seats no more than seven people. Absolutely delicious!! On Eastern Avenue between Broadway and South Ann Streets.