It is called cobblestone, which is a by-product of mining yellow sand, and it is named because it looks like a goose egg. It is a by-product of mining yellow sand, hence its name, because it looks like goose eggs. As a kind of pure natural stone, pebbles are taken from the gravel mountain produced by the uplift of the ancient river bed after the crustal movement thousands of years ago, and they are constantly squeezed and rubbed during the transportation of mountain torrents and running water.

Cooking food with stones is called "stone cooking", which is an original cooking method in ancient China, and its history can be traced back to the Paleolithic Age. It is a cooking method that uses slate and stones (pebbles) as cookers and indirectly uses the heat energy of fire to cook food.

One is external heating, that is, the stones are piled up and heated, then the food is buried and wrapped tightly, and the raw materials are matured by internal thermal radiation; One is the internal heating method, that is, the stone is burned red and then filled into food (such as cattle and sheep viscera), and it is cooked by heating.

There is also a cooking method of burning stones, that is, digging natural stone pits or pits, or filling raw materials with water in containers such as tree barrels, and then adding red-hot stones to boil water to cook food.

Extended data:

In ancient times, when the Dai people held a cattle hunting ceremony, they first dug a hole in the ground, put the peeled cowhide in the into the pit, filled it with water and put the meat away, and then threw the red-hot stone into the water. One by one, until the meat is cooked, everyone will sit around and eat. This is a "stone cooking method" in which water is boiled by burning stones.

In ancient times, there was a stone pot dish that didn't need to be boiled, but it was recorded in the Book of Rites: "Rites begin with eating everything, and its scorching millet hits the dolphin." Zheng Xuan, a Han Chinese, noted, "The ancients didn't have a kettle, so they put rice and meat out and ate them in burning stones. Today, northern pheasants still exist. " This method of burning kang directly on the stone is the oldest method of burning valley on the stone in China.

In addition, there were "sand buns" in Yingcheng, Hubei Province in the Tang Dynasty. The preparation method is unique. It uses flour, oil, salt, sugar or lard to make cake blanks, and then stir-fry the cake on pebbles heated with oil until they get hot and smoke. It is characterized by light yellow color, concave-convex shape, crisp and soft, easy to digest, convenient to carry and long-lasting storage.

There is also the famous dish "Steamed Sheep with Willow" in the northwest minority areas in the Yuan Dynasty, and the "natural cake" in Shaanxi in the Qing Dynasty. The name "natural cake" comes from "cake lined with natural stones".

References:

Baidu Encyclopedia-Shi Peng

References:

Baidu encyclopedia-pebbles