The groove extending from the center removes fat and moisture from the meat, resulting in delicious grilling.
Because it has good heat retention, it is difficult for temperature differences to occur in the oil, and the heat is evenly transmitted, so it bakes evenly.
The surface of ironware is covered with fine irregularities. Oil soaks in here, and heated air also gets in to prevent burning.
The more you use ironware, the better the oil becomes compatible with it.
When cooking with ironware, iron gradually dissolves into the food in the form of ions from the surface.