La Tecla
This popular veteran of the city's modern Mexican culinary scene is still a mainstay for reasonably priced, consistently well-prepared dishes like huitlacoche risotto with corn and poblano chiles, and grilled prawns with a sweet-spicy tamarind-guajillo reduction. The space is refined, relaxed, and ideal for conversation, and there are a few tables on the sidewalk overlooking Plaza Villa de Madrid and Fuente de Cibeles.