Recipe
Soy sauce 1000ml
Mirin 600ml
Bonito flakes (Katsuobushi) a handful
Put 600ml of Mirin in a pot and boil it.
Add 1000ml of soy sauce after it boils.
Turn off the heat before it boils.
Add a handful of bonito flakes(Katuobushi).
Leave it for a day.
Strain it with a sieve or paper towel to remove bonito flakes.