Measuring and/or monitoring food doneness using ultrasound. The present invention provides a method, system, computer program product and sensor for measuring and/or monitoring the degree of food doneness. The present invention provides means for non-invasively and continuously determining the degree of food doneness using ultrasound technology. In general, the present invention works by applying ultrasound signals to a food item, receiving the ultrasound signals emitted back from the food item, and analyzing the input and output signals to determine the degree of food doneness. The food doneness sensor can be a stand-alone device, embedded into a cooking tool, embedded into a cooking apparatus, and/or embedded into a food production assembly line. The present invention can be used personally/commercially. User feedback regarding the performance of the present invention can be provided to a cloud database and used to modify/adjust the measuring/monitoring process. Finally, multiple ultrasound sensors/transponders can be coupled together.