During the reign of Emperor Wu of Han, Liu An, the grandson of Han Gaozu Liu Bang, inherited his father's title as King of Huainan. He likes to recruit talented people, and there are often thousands of diners under his sect. In order to solve the problem of eating for so many people, they invented tofu using salt and brine produced in the Huai River Basin as a coagulant.
By the time Fushun was established as a county due to salt in the second year of Tianhe reign of Emperor Wu of the Northern Zhou Dynasty, its salt production had already ranked first in Jiannan Road (equivalent to some areas of eastern Sichuan and Chongqing today). The salt industry has seen an increase in handicraft workers, residents, and merchants, with convenient land and water transportation, resulting in a significant increase in demand for tofu food.
In an accidental situation, some customers who were waiting to eat had no patience to wait for the tofu to be formed before being processed into dishes and brought to the table. They ran to the kitchen and saw the tender tofu slowly cooking in the pot, so they asked the shop owner to sell it to them.
Due to insufficient solidification, it is not possible to stir fry, so one can only mix salt with water to make the "next meal". People were surprised to find that this kind of eating method was more delicious than the fried old tofu, which was spread to the public.