250 ml dark Soy sauce, or a combination of light and dark
200 ml Yuzu (or lemon) juice
50ml rice vinegar
100 ml mirin
10 grams bonito flakes
5 grams of Konbu
Add 100 ml Mirin into small pot
When Minim starts to boil ,use lighter to light and evaporate alcohol
When fire goes out add the soy sauce and heat till just before boiling
Turn off heat and set aside to cool completely
Transfer to a jar or bowl
Add vinegar and lemon juice
Add Kombu to jar
Add bonito flakes and let them sink
Let rest for 4 days
Strain through paper towel or cheese cloth and strainer
Squeeze juice out of the Kombu and Bonito Flakes caught in the cheesecloth
Taste.If too sour for you add a bit of Mirin
Keep in fridge in bottle for months
This is a recipe by Kunihiro from his you tube channel
https://www.youtube.com/watch?v=lcS75JRBB7Y