Mentsuyu is a japanese allround dipping sauce and soup base – it seems to be a very common condiment there and it tastes great. I use it as a dipping sauce for cold Soba/Somen noodles. The following recipe is not completely original, since Kombu seaweed and Bonito flakes aren’t available here and I substituted them with plain dashi powder. But I cross-tried it in a japanese restaurant and it does come close enough.
1 cup Dashi (250ml)
1/2 cup Mirin (120ml)
1/2cup Sojasauce (120ml)
1/4 cup Sake (60ml)
1 tsp. Zucker
In a pot, heat mirin stir in the sugar to dissolve. Just before it starts to boil, add soy sauce and dashi and stir again. Again, just before it starts to bail, remove from heat, let cool and fill into a clean container.
Mentsuyu keeps well in the fridge for several weeks.