Tacos al Pastor are Mexico City's most iconic taco, all red chile-marinated pork roasting slowly on a vertical spit and sliced with glistening pineapple into a warm corn tortilla. Rick offers a glimpse of the bustling city's taco culture, from busy daytime eateries to late-night vendors. No trompo? No problem. Rick makes a version on his grill that will please al pastor purists, then it's back to Chicago for grill-roasted black cod al pastor.