How to reheat steak in the microwave
Place your steak on a microwave-safe dish with a damp paper towel loosely over it. Adjust your microwave settings to medium heat or 50% power and cook in 30-second increments, flipping your steak in between those increments. Do this for 90 seconds to 2 minutes.
The exact time for reheating steak in the microwave depends on the thickness of your steak, the wattage of your microwave and how well done you wish your steak to be. This method requires a little more effort in order to prevent drying out your steak.