A cooking method comprises heating step, which involves heating foodstuffs into pan to first predetermined temperature with the purpose of food safety, lowering heating powder so as to enter slow pan mode, then increasing temperature slowly and constantly to a second temperature of foodstuffs aging. The method further comprises allowing the main heater to stop heating after reaching the second temperature, then entering cooling step so as to lower pan temperature naturally to above third predetermined preservation temperature. While maintaining little heat source at bottom of pan during the cooling step so as to maintain convection in pan and allow foodstuffs temperature uniform.
