Toast flour for coating : In a dry pan,toast 4–5 tbsp glutinous rice flour until it turns a very pale beige and smells slightly nutty. Set aside to cool.
Prepare the filling : Divide the red beanpaste into 4 equal balls (about 20 g each, depending on strawberry size). Wrapeach strawberry with a ball of bean paste, starting from the pointed tip andcovering it completely. Set aside.
Make the mochi dough : In a bowl, combine glutinous rice flour, cornflour, sugar, and matcha powder (if using). Gradually whisk in water until smooth (add more water if too dry). Add vegetable oil and mix well.
Steam the mochi : Steam the mixture forabout 10 minutes. Halfway through, check the centre. If not fully cooked, stirwith a wooden spoon, then cover and continue steaming until translucent andsticky.
Knead the mochi : Once cool enough to handle, knead and stretch the dough until smooth.
Divide and shape : Cut the mochi into 4 equal pieces and place onto a tray dusted with toasted glutinous rice flour to prevent sticking. Flatten each piece into a round disc.
Assemble the Daifuku : Place a bean-paste-wrapped strawberry (tip facing down) onto the mochi disc. Gently gather the edges of the mochi to cover the strawberry. Pinch and twist to seal at the top. Smooth into a ball and place seam-side down, with the strawberry tip pointing up.
Serve : Dust lightly with the toasted flour if needed. Enjoy fresh!