The restaurant may be festooned with Mexican masks and lit in the soft blues and oranges of an Oaxacan twilight—but its liveliest decor is the horde of well-heeled neighbors who frequent the spot in spite of the guaranteed wait. (Cactus doesn't take reservations for parties under five.) And yes, that means the food is good, at times really good, with a list of tacos, salads, soups, and the Mexican tapas called antojitos. Entrées hail from the American Southwest and the plains and playas of Mexico, and though the kitchen will occasionally rest on laurels—producing a mushy this, an overcooked that—one can always count on the succulent tamales (which sell out early). . . and did we mention the margaritas?