<p>A cooking apparatus for performing a microwave cooking operation and a convection cooking operation wherein heated air is circulated in an oven cavity. An air intake aperture is formed at the center of the ceiling wall of the oven cavity. The air removed through the air intake aperture is heated up by a heater and reintroduced into the oven cavity through a first blowoff aperture which is positioned at the corner of the ceiling wall near a right side wall of the oven cavity, and through a second blowoff aperture which is asymmetrically positioned at the lower portion of a left side wall of the oven cavity.</p>