Place the two slices of white sandwich bread on a clean plate.
Spread 1 tablespoon of mayonnaise evenly on one side of each bread slice.
On one bread slice, layer the two slices of cheddar cheese evenly.
Add the two slices of tomato on top of the cheese.
Place the two slices of cucumber over the tomato slices.
Add the two leaves of iceberg lettuce on top of the cucumber.
Sprinkle salt and black pepper to taste over the vegetables.
Cover with the second bread slice, mayonnaise side down, to complete the sandwich.
Press gently to hold the sandwich together and serve immediately.