Tadelakt plaster walls, handwoven rugs, and zellige mosaics are nothing new in the Red City. But at the Mandarin Oriental, Marrakech, which opened in October, such traditional touches form only part of the picture. Infused with Mandarin Oriental’s high-gloss style in a sleek black-and-white palette, the hotel’s 63 suites and villas strike an intricate balance between historic Morocco and modern-day minimalism. The harmonious blend extends to the kitchen, where the Moroccan chef Meryem Cherkaoui (formerly of Pa…