American BBQ is good, but Mexican can be better -- and the high-tone norte?o costillas at Cielo are proof. These pork ribs are smoky, slow-roasted, meaty masterpieces of balance and simplicity, crusted with crushed black pepper, rubbed with chiles and piloncillo, then slathered in a thick, sweet-hot adobo-chile barbecue sauce that plays perfectly against the pork's mildness and the simple three-note harmony of the meat's dry rub. Texas, Kansas City and the Carolinas may be where most people consider the home turf of fine 'cue, but in Denver, the flavors of the pampas and the simple spice of Cielo's perfect pork ribs have put us in a sur de las Américas state of mind.