Zhang Zhongjing, a medical sage, is an official in Changsha. It happened to be the winter that year when he retired from his hometown. The wind is biting and the snow is falling. By the Baihe River, Zhang Zhongjing saw many homeless people with sallow faces and thin clothes, because their ears were frozen and rotten with cold. He was very sad.
After returning home, many people came to seek medical treatment. Zhang Zhongjing is responsive and busy all day. Although there are many people seeking medical treatment, Zhang Zhongjing still misses those who have frozen rotten ears. After research, he invented a prescription to keep out the cold, called "Quhan Joule Decoction". He told his disciples to build a shed in an open space in Dongguan, Nanyang, and put it on a cauldron to give medicine to the poor. The opening day is the solstice of winter, and the medicine given is "Quhan Joule Decoction".
Cold-dispelling pepper soup is to put mutton, pepper and some cold-dispelling drugs into a pot, take them out and chop them up after cooking, wrap them in a flour bag to look like an ear, then put them into a pot and cook the stuffed dough with the original soup. Distribute it to the poor who come to see a doctor, on the one hand, treat the disease, on the other hand, eat.
This is the origin of jiaozi.