Japanese Kashiwa Mochi and Seasonal Leaf-Wrapped Wagashi

Ingredients

• 150 g jōshinko (non-glutinous rice flour)
• 50 g shiratamako (glutinous rice flour)
• 180 ml water, warm
• 40 g caster sugar
• For the filling (choose one)
• 300 g koshi-an (smooth red bean paste), or tsubu-an (chunky red bean paste), or shiro-an folded with white miso
• 20 g white miso, folded into shiro-an only, if using that filling variant
• For the leaves
• 12 kashiwa (Japanese oak, Quercus dentata) leaves, fresh in late April–May, or salt-packed leaves soaked 30 minutes in cold water, patted dry

Method

1. 1
   If using salt-packed kashiwa leaves, soak them in cold water for 30 minutes, pat dry, then warm briefly in steam or hot water until fully supple. If using fresh leaves, wilt briefly in steam or hot water. The leaf must bend without resistance and show no tendency to crack at the spine.
2. 2
   Divide the chosen filling into 12 equal portions of approximately 25 g each. Roll each portion into a compact oval. Set aside.
3. 3
   Combine the jōshinko and shiratamako in a bowl. Dissolve the sugar in the warm water and add to the flours, mixing to a smooth, cohesive dough. The dough should be soft but not sticky, holding its shape when pressed.
4. 4
   Transfer the dough to a heatproof bowl or tray, cover with damp cloth, and steam over vigorously boiling water for 20–25 minutes. This is where the dish lives or dies: the dough must be steamed until fully translucent throughout with no white, raw core visible at the centre — under-steamed mochi has a chalky texture and will not fold cleanly around the filling; over-worked dough after steaming becomes excessively sticky and clings to the leaf, destroying presentation on unwrapping.
5. 5
   Turn the steamed dough onto a lightly dampened surface. Knead briefly while still warm until smooth and uniform. Divide into 12 equal portions of approximately 30 g each. Flatten each portion into a round disc in the palm.
6. 6
   Place one filling oval at the centre of a mochi disc. Draw the edges of the mochi up and around the filling, pinching to seal completely. Shape into a smooth oval. The filling should be fully enclosed with no gaps at the seam.
7. 7
   Place each filled mochi oval onto the underside (dull face) of a prepared kashiwa leaf, positioning it at the centre. Fold the leaf lengthwise over the mochi, overlapping the edges at the spine to seal the aroma in. Press the fold gently so the leaf holds. Present with the fold facing the guest. The mochi should hold its oval shape and the leaf should show no tears.
8. 8
   Serve within hours of making. The kashiwa leaf's aromatic transfer to the mochi is active while the leaf is fresh and supple; the subtle green, tannic note should be perceptible when the leaf is opened. Day-old leaves lose aromatic relevance.