The traditional method that costs zero is just to pour the batter after a drop of water shows the Leidenfrost effect and before the pan starts to smoke. Laser

The traditional method that costs zero is just to pour the batter after a drop of water shows the Leidenfrost effect and before the pan starts to smoke. Laser thermometers are fun though. https://en.wikipedia.org/wiki/Leidenfrost_effect https://en.wikipedia.org/wiki/Leidenfrost_effect