The winning Mandarin formula—exemplary service, forward-reaching design, a first-rate spa—has taken root in a pristine Mexican coastal environment. Acres of mangrove forest, including an on-site cenote, surround a lovely—albeit small—stretch of powdery sand. The 128 boxy white villas give beach chic new meaning, with polished stone floors, rough limestone walls, spare four-poster beds, and sculptures by prominent Mexican artists. We’ll admit, we did experience a bit of sticker shock at checkout. But it’s worth it. This is the most sophisticated resort on Mexico’s eastern coast.