A method of regulating the temperature of a cooking liquid during sous vide cooking in a cooking vessel on a burner of a cooktop includes setting a desired cooking temperature and measuring the temperature of the cooking liquid inside the sous vide cooking vessel at a plurality of predetermined time intervals with a first temperature sensor mounted on an interior surface of a wall of the sous vide cooking vessel. The temperature of the cooking liquid is compared to the desired cooking temperature at each of the predetermined time intervals. The energy output of the burner is controlled based on the difference between the temperature of the cooking liquid and the desired cooking temperature. A cooking vessel and system for sous vide cooking using this method are also disclosed.