Steps
1. Heat a non-stick pan over medium heat.
2. Spread margarine on one side of each bread slice.
3. Place one slice of bread, margarine side down, on the pan.
4. Add a layer of cheese on top of the bread.
5. Crack open an egg on top of the cheese.
6. Cover the pan and cook for 3-4 minutes, or until the egg white is set.
7. Remove the sandwich from the pan and spread mayonnaise on the other slice of bread.
8. Place the mayonnaise side of the bread on top of the cooked egg.
9. Slice the sandwich diagonally and serve.