Chicken in Sweet-Tart Sauce

When I’m in Mexico exploring a spot new to me, I always start by asking people who’s the best cook in town. I tried it in Tuxpan, a Huasteca-area river town that I always think of as the city of spectacular sunsets. The invariable answer was “Angelita” — Doña Ángeles Juárez Molina. This gracious, efficient woman, a former president of the city restaurant association, runs a rosticería, a place specializing in rotisserie-broiled chickens. (Yes, rotisserie shops are as popular in Mexic