The casserole can transfer the external heat energy to the internal raw materials in a balanced and lasting way. The relatively balanced ambient temperature is conducive to the mutual penetration of water molecules and food. The longer the mutual penetration lasts, the more delicious ingredients spill out, the more fresh and mellow the soup will be, and the texture of the cooked food will be more crisp and rotten.

The traditional casserole is a kind of pottery. The invention of pottery is an epoch-making symbol in the history of human social development, and also the greatest invention of human development. It is said that Emperor Yao invented the casserole, which has a history of thousands of years.