Mongolian milk tea (奶茶, naichá in Chinese; suutei tsai in Mongolian) is not the sweet bubble tea associated with Taiwan but the traditional pastoral drink of the steppe: brick tea (compressed dark tea, often roasted) simmered with milk, salt, and sometimes butter or millet. The result is savoury rather than sweet — closer to a broth than a beverage — and it takes adjustment if you are expecting anything resembling European-style tea with milk. The salt is essential and sufficient; asking for it without is missing the point.
In Hohhot, the traditional milk tea is served at the better Mongolian restaurants and at tea shops near Dazhao, where the correct preparation is done over a low flame rather than by pouring hot water. The most common accompaniment is fried dough twists (炸果子, zha guozi) for dipping. A sit-down milk tea service at one of the traditional teahouses near the temple is worth the fifteen minutes it takes; the alternative is the instant-powder version sold everywhere in Inner Mongolia, which is not the same thing.