Start by spreading butter or margarine evenly on one side of each slice of bread.
Place one slice of bread, buttered side down, on a microwave-safe plate.
Layer the cheese slices on top of the bread on the plate.
Place the second slice of bread on top, buttered side up.
Microwave on high for 30 seconds. Check the sandwich; if the cheese isn’t melted, continue microwaving in 10-second increments until melted.
Carefully flip the sandwich over and microwave for an additional 10-20 seconds to heat the other side.
Once done, let it cool for a minute before slicing in half and serving.