A speed cooking with improved gas flow by-pass mechanism for radiant cooking mode. A speed cooking oven with radiant mode is disclosed comprising a cooking cavity, a controller, thermal heating source, blower assembly, air directing means, a vent assembly and a single door gas by-pass system. Hot gas is circulated by the blower motor assembly into the oven cavity where the hot air is directed in a manner wherein a conflicting, colliding turbulent gas flow is directed at a food product providing for the rapid cooking of food products. Alternatively, a single movable door may be utilized that operates between an open position wherein gas flow exhausts from the top of the oven or in the closed position wherein gas is diverted through a conduit and back to the blower mechanism. Gas may therefore flow into the oven cooking cavity or may be diverted around the cooking cavity and maintained at the same temperature, lower temperature or elevated temperature as compared to the cooking cavity without having a direct effect on the food product being cooked.