Wireless temperature sensor for sous vide cooking. Wireless sensor penetrates food and is sealed with the food in a bag for sous vide cooking. The wireless sensor communicates with the base sous vide system to read core food temperature to ensure pasteurization temperature and time is reached and to eliminate estimations with fat content, size of food in relation to cooking time by taking a direct read. The temperature sensor contains a battery, powered passible via peltier, or through induction.