Make s'mores in a microwave for a graphic demonstration of a microwave's power of cooking food through all at once: the marshmallow rapidly becomes extremely large.
Cook something big (but not huge, leave plenty of space on the sides, and stack loosely so some microwaves can enter into the core of the pile) at full power. For instance, a few pounds of potatoes to be mashed, piled all together plastic wrap or washed and returned to a plastic bag they came in, at full power. (Try fifteen minutes on high for five pounds.)
Microwave chopped-to-size vegetables before frying them to get the inside somewhat soft without having to burn the outside.