"Famous Cuisine in Ancient and Modern Xuzhou" records that when Su Shi became well-known in Xuzhou, the Yellow River burst, and Su Shi took the lead in building dikes to protect the city with the people of the whole city. Xuzhou people slaughtered pigs and sheep and went to the government to comfort them. Unable to refuse, Su Shi instructed his family to cook braised pork and return it to the people. After eating, people feel fat but not greasy, crispy and delicious, so they call it "Sichuan style pork". When Su Shi demoted Huangzhou, he sang "Cooking Meat": "Huangzhou is a good pork, and its price is as cheap as dung. The rich refuse to eat, and the poor don't know how to cook. Slow fire, less water, beautiful when the fire is enough. People began to imitate each other and dubbed it "Dongpo Meat".
So Dongpo pork is a way of braising in soy sauce.