There are two important things in this recipe: Boil the egg for exactly the right amount of time. The yolk must be bright yellow and be uniformly cooked and solid. Over or under boiling the egg by even 30 seconds can ruin the taste and texture. Undercooking can mean that the yolk will have  liquid or semi-solid parts. Overcooking will make the yolk turn light yellow. The second important thing is to infuse the flavour of the tomato into the Olive oil and the toasted bread.

Some trial and error may be required to get the boiling right because this depends on the ambient temperature, atmospheric pressure and size of egg. Generally I keep the egg in a small vessel filled with water and once it comes to a boil I reduce the flame and keep it for 7 minutes. At the end of 7 minutes, empty out the hot water and fill the vessel with cold water and then keep for 10 minutes before peeling. Add some salt to the water to raise the boiling point.

Toast the bread in a toaster till brown

Apply 1 tbsp extra virgin olive oil in a non stick pan and place the tomato slices on it. Keep the heat on low. After a minute or so, add the toasted bread into the pan, turn the tomato slices over and cover the pan. Keep for a further minute and turn off the heat. Let the pan remain for 3 - 4 minutes.

The bread absorbs moisture (and flavour) from the tomato and becomes flexible so that the sandwich can be stuffed. The tomato flavour also infuses into the oil which you will later pour over the egg.

Generally refrigerated cheese slice or cube / tin gives a more intense flavour if you keep the cheese at room temperature for some time. I usually allow the cheese to come to room temperature before using it.

Apply butter to the toast. Place the cheese and tomato slices on one of the bread slices. Add some salt to the tomato slices. Place the boiled egg on top and cut it with a knife. Add salt and pepper on the egg. Pour the remaining olive oil over the egg. Place the other slice on top and enjoy.