Get Shokupan from Suzuya which already cut into slices. Cut the crust off and leave only the white area.

After boiling eggs on medium heat for 12 min, transfer the eggs to iced water to cool completely. And then peel eggshells.

Transfer the peeled eggs to a bowl and mash. Try to mash the egg whites into small, same-sized pieces.

Add the mayonnaise and mix very well.

Spread the butter on both slices of bread. Evenly distribute the mixed eggs on one slice of bread.

Cut the Shokupan in half and your Egg Sando is ready to serve!