Cut the avocado in half, remove the pit, and peel the skin.
Slice or mash the avocado as desired.
Wash the tomato and lettuce and slice them into bite-sized pieces.
Toast the bread in a toaster or pan until warm.
Place the avocado on the bread and season with salt and pepper.
Add tomato, lettuce, or other preferred ingredients as desired.
Cover with another slice of bread to complete the sandwich.