It's called square cake.

According to a search of China's eight major cuisines, the white dessert at the Anhui banquet is the Yunling Square Cake, a specialty delicacy in Jingxian County, Anhui. It is made of glutinous rice, sesame and white sugar. The Yunling Square Cake has a light and refreshing fragrance and a sweet taste.

Anhui Province, referred to as "Wan", is a provincial-level administrative region of the People's Republic of China and the provincial capital Hefei City, located in the Yangtze River Delta region of East China.