Start by filling a saucepan with water and bringing it to a gentle boil over medium heat. Carefully add in the large eggs and let them cook for about 9 minutes.

Once the 9 minutes are up, quickly remove the eggs from the boiling water using a slotted spoon and plunge them into the ice bath for around 5 minutes.

Peel the chilled eggs under running water to help remove the shells easily. Roughly chop the eggs and transfer them into a mixing bowl.

In the bowl with the chopped eggs, add Kewpie mayo, honey, rice vinegar, salt, and black pepper. Stir gently to combine.

If you prefer a crispy texture, lightly butter the milk bread slices and toast them in a skillet until golden brown.

Spread a generous layer of the creamy egg salad onto four slices of toasted or fresh milk bread. Optionally add thinly sliced cucumbers or scallions.

Carefully cut the assembled sandwich into halves or thirds, and serve immediately.