Taqueria El Rey on Vernor in Mexicantown is one of the better cheap-and-cheerful taco stops in southwest Detroit. The barbacoa (slow-cooked goat) is the order — served with consommé for dipping the soft tortillas. The al pastor and lengua are also good. The room is small, the menu in Spanish, and the place busy at lunch.
Several other strong Mexicantown options sit within a few blocks: Taqueria Mi Pueblo, Los Galanes, Mexican Village. El Rey is the no-frills end of the spectrum. Cash preferred.