2 slices bread
1 slice American cheese
1 tablespoon mayonnaise
Heat a small skillet to medium.
Using a butter knife, spread half of mayonnaise onto one slice of the bread. Place bread mayonnaise side down in the skillet. Top with cheese.
Spread remaining mayonnaise onto second slice of bread and place mayonnaise side up on top of cheese. Cook 3 minutes, or until bread is toasty brown. Flip the sandwich and repeat on the other side.
Note: Miracle Whip does not work for this, as the sugar in it tends to burn.