Top with a slice of cheese, then 2 slices of ham and finish with the second slice of cheese.
Fold the lettuce leaf so it fits the bun and place on top
Close the sandwich with the other half of the bun
Place in a toaster or grill pan and gently press so both sides of the bun get toasted evenly
Notes
If you like your cheese to be melted, place the cheese in the microwave for 15-20 seconds before adding to the sandwich. You could add some pickled cucumbers if you prefer or have them on a side when serving the sandwich