Preparation:
1. Prepare the rice - wash the rice thoroughly until the water becomes clear. Soak the rice in water for about 15 minutes, strain the rice and add the 6 cups. of water and cook in rice cooker.
2. Prepare the vinegar -mix all of the ingredients in a saucepan and bring to the boil.
3. Mixing the rice - put the cooked rice into a hangiri (cedarwood rice-cooking tub) or other non-metallic container, spread it out evenly in a ploughing manner (left-right, top-bottom) with a large wooden spoon, while doing so, slowly add the sushi vinegar until the rice sticks together without being mushy. Rice should remain at body temperature.
4. Prepare soy sauce - mix all the ingredients together except the katsuobushi in saucepan and bring to boil. Add katsuobushi, remove from heat. Once the mixture is cool, filter it through a strainer.