I make this for a 4-person family whenever I run out of store-bought soba tsuyu (dipping sauce).
For soba or somen noodles.I think I saw this in the newspaper or a magazine about 10 years ago.Or at least that's about how long ago I took down the recipe.
For dipping sauce, use this recipe as is. If serving the noodles in the sauce, dilute with 4 times as much dashi stock.
Enjoy Japanese food around the world.