Kewpie is Japan’s most trusted and beloved mayonnaise and salad dressing brand,and has been a staple of Asian cuisine since we introduced mayonnaise to the Japanese kitchen in 1925.
In a bowl, mash the eggs with a fork. Add 2 Tbsp of mayonnaise and mix. Season with salt and set aside.
On each side of the shokupan slices, spread the rest of the mayonnaise. Place the egg/mayo mixture evenly on the shokupan, and cover with another piece of shokupan, mayonnaise side down. Cut into half and serve.