Crystal cake, a crispy dessert, gained its name from its crystal-like transparency. Crystal cake is golden on the surface and white like snow all around; meanwhile it has the aroma of rose and fine scent of orange. It is recognized as the most popular Shaanxi dessert.

The snack rose to fame thanks to Kou Zhun, prime minister of the Northern Song Dynasty (960-1127). He became a successful candidate in the highest imperial examinations at the age of 19 and took up his post as prime minster in 1004. He was renowned for his honesty and integrity as an official.

Once upon a time, Kou happened to have his 50th birthday when he returned to his hometown in Weinan from Bianliang, capital of the Northern Song Dynasty. He offered a feast to those fellow villagers coming to celebrate his birthday. During the meal, a gift box was presented to him and he found 50 crystal cakes in it. There was a paper praising Kou's integrity and clean hand. It was inscribed: an old man from southern Shaanxi.

Kou was grateful for the praise and took it as a reminder to stay honest and clean. Since the snack is crystal-like, he named it crystal cake, after which the name stuck.

People can buy the most authentic taste of the food in Demaogong, a renowned brand of the delicacy in Xi'an. It is a typical local snack and was once as famous as edible bird's nest, tremella and Jinhua ham.

Over the past 130 years, Demaogong has become more renowned and creditable due to its virtue, diligence and humility in business.