Do this
Put 10 g of kombu in 1 liter of cold water. Cover it. Leave it in the fridge for 8 to 10 hours. Lift out the kombu.
Why it works
Umami slips out even in cold water. The slimy fiber needs heat to melt. So a cold soak gives a clean, clear stock.
When to skip it
Skip it when you need dashi within the hour. Use the 60C method instead.
