The secret is in the unique way microwaves work. Conventional ovens heat up the air inside the oven first then heat up the surface of the food and then heat up the inside. Microwave ovens cook the inside of the food right away, without heating up the surrounding air. They do this by using high frequency electromagnetic waves.
Have you ever noticed that when you eat hot chili it dulls the flavors of other things? In this Moment of Science we explain why that is.