While the muffin is toasting,
break the egg onto a saucer and beat it lightly with a fork.
You can beat the egg in a small
bowl if you find this step messy, but you're going to cook it in the
saucer so it will be flat and round. (beating it in the saucer saves
you a dish to clean).
Microwave the egg, on the saucer,
on high for 30 to 60 seconds, until it just set and a bit puffy.
Butter the toasted muffin and lay
the cooked egg on the bottom half.
Lightly salt and pepper the egg,
and then lay the cheese slice on top.
Top with the other muffin half and
eat immediately.