Cook dried Soba according to the package. Rinse under running water and strain well.

While cooking Soba, slice Shiso leaves thin and finely. Grate Nagaimo with fine grater. Separate egg yolks and whites.

Place cooked Soba in a deep bowl, add grated Nagaimo, a yolk, and Shiso. Pour Mentsuyu (diluted by the equal amount of water). Add a little Wasabi if you like.