PURPOSE: To enable efficient rotating in a covered part by housing materials to be cooked between a top plate which is electromagnetically induction-heated and steamer boxes which are hermetically closed by freely openable and closable magnet switches disposed thereon and disposing liquid injection nozzles on the inner side of these steamer boxes.

CONSTITUTION: The top plate 12 to be used as a cooking table is formed of a magnetic material having high flatness of the surface and forms hermetic spaces with the steamer boxes 10. Cooking materials are placed on the top plate 12. The top plate 12 and the steamer boxes 10 are brought into tight contact by the magnet switches 13 and contact springs 15. The top plate 12 is then electromagnetically induction-heated and water or required seasonings are injected at prescribed timing by a liquid volume controller 18 from the liquid injection nozzles 11. The temp. and liquid volume are controlled by controllers 17, 18. Kick-up arms 14 maintain the steamer boxes 10 at an open state before the start of cooking.