Rinse the dried adzuki beans and add to 700 ml water in a sauce pan. Simmer over medium heat. When it comes to a boil, add 200 ml of water. When it comes to a boil again, turn off the heat and drain.
Put the adzuki beans into the pan again, add water to 2 cm above the beans. Simmer over medium heat until the beans lose their wrinkles and become smooth, and drain.
Put the adzuki beans into the pan again, add water to 2 cm above the beans. Simmer over low heat until the beans become tender enough to easily mashed with your finger. Always simmer over low heat.
When the adzuki beans are tender, add salt and sugar and simmer for 15 minutes. Add the sugar in 3 batches. Leave to stand overnight to let the flavors meld together. And it's ready.
Toast mochi until golden brown. Put the mochi in the sweet red bean soup and enjoy.
You can make sweet red bean soup from anko (Recipe ID: 1325858).
Story Behind this Recipe
You can make zenzai from homemade sweet adzuki bean paste dissolved in hot water, or make it from scratch by cooking adzuki beans.
In Step 2 and Step 3, if the water level becomes too low, add water to cover the beans. Keep the beans covered with water all the time.