There’s nothing quite like a warm bowl of oshiruko—sweet red bean soup with mochi—to soothe the soul on a chilly day. This classic Japanese comfort food is gentle, cozy, and just the right kind of sweet.
In this version, I add a little twist with shio koji, a fermented seasoning that brings out a deeper flavor. It adds a touch of saltiness, subtle umami, and even enhances the natural sweetness of the red beans, making each bite feel even more satisfying. Whether you’re familiar with oshiruko or trying it for the first time, this recipe is a comforting hug in a bowl.

Red Bean Soup with Mochi (Oshiruko) Using Shio Koji
Ingredients
- 140 g (4.9 oz) sweetened red bean paste (anko)
- 80 ml (2.7 floz) water
- 1 tsp (1 tsp) shio koji
- 1 block (1 block) rice cake (mochi)
directions
- Add sweetened red bean paste into a small pan.
- And then add some water, little bit at a time. We want just enough water to smooth out the bean paste. I like my soup to be thick, but make it as thick or thin as you like.
- Turn on the heat to low and mix until the red bean paste and water are mixed well together. When the soup looks like this, we are pretty much done with the soup.
- Add a little bit of shio koji. This adds depth to the flavor.
- Pop rice cake (mochi) into a toaster and bake it at 230 °C (446 °F) for 5 minutes or until it becomes soft and puffy.If you don't have a toaster, you can cook mochi in the microwave oven or on a frying pan too.
- When your rice cake is puffy and lightly charred at the top, it's ready!
- Add the hot soup into a small bowl, and then add mochi on top. And we are done!
Recipe Notes
- Feel free to adjust the ingredient amounts to your taste.
- What Is Shio Koji? (The Complete Guide)
- How to Make Shio Koji (Recipe)
- Shio koji products: – If You Are Outside of Japan Shio koji by marukome 200g (7.05 ounce): https://geni.us/8vWX0vj Shio koji by marukome 500g (17.6 ounce): https://geni.us/tIoxH2b – If You Are in Japan Shio koji by marukome 500g (17.6 ounce) x 2: https://geni.us/Kbbw0C
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Nutrition
Hi! I’m a Japanese woman who lives in Tokyo. My passion is cooking and eating food. Read more about me at https://sakurayubi.com/about/