Question:How does infrared radiation cook food?
Infrared radiation is absorbed at the surface of the food.
The absorbed energy from the infrared radiation increases the Kinetic/vibrational energy of the particles at the surface of the food, which increases the temperature of the surface of the food.
All the rest of the food beneath the surface is then heated by conduction of heat from the warmer surface to the colder interior.
This means the surface of food is always hottest and this is why food tends to brown or burn at the surface but not on the inside.