Disclosed are cooking devices and methods for measuring and controlling the humidity content using a temperature/humidity probe in the cooking devices. The temperature/humidity probe operates in a closed system so that heat and humidity is not lost excessively to the outside environment. The temperature/humidity probe confers energy savings and efficiency to the operation of the cooking devices. One embodiment provides a closed system in which the end of a drain pipe disposed between the cooking chamber of the cooking device and a condenser outside of the cooking chamber is below a water level in the condenser so as to form a closed system such that heated and humid air in the cooking chamber cannot exit the cooking chamber without passing through the water level, and the temperature/humidity probe is disposed in the condenser in an air space above the water level and proximal the drain pipe.
