Possibly the most ambitious of Hugo Ortega’s restaurants, Xochi occupies a lovely, elegant setting in the posh Marriott Marquis Houston, across from Discovery Green park. We recently sampled some fine dishes and a few that were less than stellar. Top marks went to the moist and hearty cachetes de res (braised beef cheeks with mole pasilla) and the sopa de piedra, literally “stone soup,” with smooth, hot stones in the broth and huge heads-on shrimp hiding behind them. Less successful was the barbacoa de res de Zaachila, braised skirt steak that came rarer than ordered and tougher than expected. We liked our molotes de Xoxocotlán, sturdy masa cakes with potato, chorizo, avocado, and queso fresco, but the Huitlasquites, corn soup with huitlacoche, mayo, and queso fresco, seemed to lack much corn flavor. Don’t miss the Piedras y Oro, a chocolate tart with a crocant of mixed nuts, praline, and rocks made of chocolate.