Laodatong Restaurant (Heyang Street Branch). In Datong City, the brown sugar cakes in the Old Datong Restaurant (Heyang Street Store) are crisp outside and tender inside, and the sugar does not flow out. The layers are distinct and very delicious. Datong, formerly known as Yunzhong, Pingcheng and Yunzhou, is a prefecture-level city under the jurisdiction of Shanxi Province and one of the provincial sub-central cities established by the Shanxi Provincial Government.