Wife Cake (Lao Po Bing / 老婆饼)

Make the winter melon paste. Cook the winter melon flesh over medium heat, stirring, until all moisture has evaporated and the mass is dry. Add the sugar and continue to cook, stirring constantly, until the mixture is dense and cohesive. Remove from the heat and fold in the toasted sesame seeds and melon seeds. Cool completely. The paste is ready when it holds its shape cleanly under pressure without crumbling.

Make the water dough. Combine the flour, icing sugar, and lard, then add cold water and bring together into a smooth, pliable dough. Rest covered for 20 minutes. The dough is ready when it is soft and extensible, with no dry patches.

Make the fat dough. Work the lard into the flour until a cohesive, soft dough forms — it should be pliable but not greasy to the touch.

Divide each dough into 12 equal portions. Flatten one water-dough portion and wrap it around one fat-dough portion, sealing the edges completely. Roll the enclosed piece into a thin oval, then roll it up into a cylinder. Turn 90 degrees and roll again into an oval, then roll up once more into a compact cylinder. This two-stage roll-and-fold builds the paper-thin layers that define the pastry. This is where the dish lives or dies: incomplete rolling or torn seams will collapse the layer structure, and no subsequent step can recover it.

Press each cylinder flat, then roll into a round disc approximately 10 cm in diameter. Place a portion of winter melon paste at the centre — do not overfill. Gather the edges of the disc upward around the filling and pinch firmly to seal. Gently press into a slightly flattened round and place sealed side down on a lined baking sheet.

Score two parallel cuts across the top of each cake with a sharp knife, cutting through the outer layer only. Brush with egg wash. Sprinkle sesame seeds over the surface. The scored surface should appear cleanly split, revealing the layers beneath.

Bake at 180 °C until the cakes are golden and the layers at the scored openings have separated and crisped visibly. The surface should be a deep, even amber; the pastry should feel firm but not hard when lightly pressed at the side.

Transfer to a wire rack and cool to room temperature before serving. The pastry achieves its maximum flakiness at room temperature, not refrigerator-cold.