There’s room in Dallas for more restaurants that focus on regional Mexican cuisine, which is why I was excited when El Bolero opened last year in the Design District with a menu that ranged from enchiladas verdes to grasshopper salsa-topped scallops. The kitchen turns out some good staples: lush, dark mole; fresh masa tortillas; taco meats shaved from a trompo. Unfortunately, on a night when unhurried, personable service and the charm of the patio made for a languid evening al fresco, there were no hits like that to be found among the starters. A shrimp aguachile was flat, tired, and boring. Queso fundido was something to keep you busy while you awaited entrées. But order cochinita pibil, a Yucatán specialty, and a banana-leaf parcel opens to reveal braised pork far upstaging the plate’s puréed beans and rice. The kitchen’s take on a chile relleno is no battered, cheese-laden torpedo, but something astonishingly light, its crab filling delicately accented with sautéed onions and tomatoes and its chile’s grassy vibrancy spared from the fryer. (Richness comes from a squash-blossom purée; pickled onions add bite.) Order dessert if you’re intrigued by the novelty of arroz con leche cake. Mostly, its creamy, cinnamon-y layer of rice pudding made me want a bowl and a spoon.