Buckwheat soba, shoyu-based sauce

Buckwheat is not real wheat, in fact, buckwheat is not even a grass. Its triangular seed is ground to powder. 

The noodles and sauce are cold. 

Sauce

* soy sauce

* rice vinegar

* fish sauce (a few drops, or anchovy paste)

* sugar (or honey, or brown sugar)

* horseradish (tastes exactly like wasabi)

* sesame oil (a few drops)

* water

You can add a teaspoon cornstarch heat in a microwave and and the sauce will thicken right up, but I like it watery.