Valladolid's food is distinctively Yucatecan and worth treating as one of the reasons to be here. The signature dishes — lomitos de Valladolid (pork loin in a tomato-and-pepper sauce), longaniza (a spiced, lightly smoked sausage), pollo en escabeche (pickled chicken with sour orange and oregano), and cochinita pibil (pork slow-roasted in banana leaves with annatto) — are easier to find here, and better cooked, than in most of the country.
The cheapest, most reliable eating is at the Mercado Municipal (north-east of the plaza) and the food stalls inside the Bazar Municipal on the north side of the square — both packed at lunchtime, both excellent. For a proper sit-down meal, Conato 1910 on Calle 40 and Yerbabuena del Sisal on Calzada de los Frailes are reliable; Taberna de los Frailes, set in a colonial garden, is the most atmospheric for an evening. Save room for a marquesita from the plaza vendors at night.