Steps

1. In a microwave-safe bowl, add Shiratamako (Glutinous Rice Flour) 100g and lightly crush it with your hands until there are no lumps. (This is key!) Crushing the lumps of shiratamako beforehand makes it easier to mix with water later.
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2. Add Sugar 70g and mix well with the shiratamako, crushing any sugar clumps. (This is key!) Mixing with sugar first helps the shiratamako blend better with the water.
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3. Gradually add Water 170ml a little at a time in several portions, mixing well each time to break down any shiratamako lumps. It will initially form a dough-like ball, and eventually become a thin liquid. (This is key!) Adding all the water at once makes it difficult to break down the shiratamako lumps, so be sure to add it gradually and crush the dough-like parts thoroughly.
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4. Cover the bowl with plastic wrap, leaving one small opening for steam to escape, and microwave on 600W for 2 minutes.
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5. While heating, line the inside of a container (approx. 15cm x 10.5cm) with plastic wrap.
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6. After heating, remove the plastic wrap and use a rubber spatula to knead the mixture thoroughly, breaking down any solid parts and incorporating them with the liquid until smooth. (This is key!) Kneading the mochi well after heating creates a smooth texture.
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7. Cover with plastic wrap again, leaving one small opening for steam, and microwave on 600W for another 2 minutes.
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8. After heating, remove the plastic wrap and knead the entire mixture thoroughly until smooth. It's ready when the mochi looks translucent and glossy. (This is key!) If it still looks whitish, microwave for another 30 seconds to achieve transparency and gloss.
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9. Sprinkle Kinako (Roasted Soybean Flour) (to taste) into the prepared container.
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10. Transfer the warm mochi into the container, sprinkle more Kinako (Roasted Soybean Flour) (to taste) on top, and cover loosely with paper to prevent drying. Let it cool completely. For faster cooling, refrigerate for 30 minutes to 1 hour. (This is key!) Cooling the mochi gives it the right firmness and chewy texture, similar to Shingen Mochi.
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11. In a separate microwave-safe bowl, combine Brown Sugar 40g and Water 25ml, and mix lightly. (This is key!) If using block brown sugar, chop it finely.
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12. Microwave on 600W for 1 minute.
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13. After heating, stir well until the brown sugar has completely dissolved. It will be watery but will thicken as it cools. Cover with paper and let it cool completely.
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14. Remove the cooled mochi from the container and peel off the plastic wrap. Flip it over.
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15. Dust the areas without kinako with Kinako (Roasted Soybean Flour) (to taste).
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16. Lightly dampen a knife and cut the mochi into your desired bite-sized pieces.
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17. Arrange the cut mochi on a plate, pour the cooled and thickened black syrup over it, and serve. It's ready!
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