One of the amazing homemade food in Japanese kitchen is absolutely miso. It is so simple to make but needs love and care for sometime. This is the miso recipe that I have learn when I started a job as a cooking teacher in Japan, and I have been making one a year since them.
Wash the soybeans well, put it in a large soup pot with 2.5 double amount of water. Soak it for 12 hours.
Next day, bring the large pot and water inside over a gas stove start heating up with a low heat until beans are easier smashed with fingers.
In a large bowl, scramble koji using hands and mix with salt, but leave 1/2 of salt on the side.
When the soybeans are soft, drain the water, but please keep the boiled water.
Put the hot cooked soybeans back into the large pot and add 3 cups of boiled hot water.
Using a handy mixer, smash all the soybeans in the pot, if no handymixter use a food processor. After smashed, it looks like rough texture of hummus.
When the soybeans are cooled, add the koji and salt mixture from #3. Mix it well using a wooden spatula. Ideal texture is just like clay softness.
Bring a large container swipe inside the container all over with a bit of sake on surface.
Make big round balls of the soybean mixture, just about a softball size. and throw it into the container until all the soybeans mixture is gone. some where between soybeans balls, place a cut of kelp.
Drop the balls into hot boiling water. When the balls start to float, pick them up and add in ice water bath. Then, drain to use.
For presentation, scoop out one or two scoops of matcha ice cream into a cup. Put two to three mochi balls and 1 tbsp of red beans paste. Garnish with a bit of matcha powder and serve immediately.