Custard Egg Sandwich on Shokupan is a delightful Japanese-style sandwich that combines creamy custard filling with fluffy shokupan bread. The custard filling is made with eggs, milk, sugar, and vanilla extract, creating a rich and velvety texture. The shokupan bread is soft and pillowy, providing the perfect base for the custard filling. This sandwich is a popular choice for breakfast or as a sweet treat throughout the day.