Wife Cake (Lao Po Bing, 老婆饼)

Make the filling:

1. Cook the glutinous rice flour for 15-20 minutes on low to medium heat in a non-stick pan, until it turns a light tan color, stirring often and adjusting the heat level as needed so it doesn’t burn.
2. To coarsely puree the winter melon, peel/cut the rind off the winter melon, and remove any seeds. Cut into chunks and transfer 250g (8.8 ounces) to a food processor. Pulse a couple of times until you get a coarse puree.
3. Transfer the winter melon to a non-stick pan over medium heat. Add the sugar, water, and coconut oil, and cook for 10 minutes. The mixture should be bubbling, thickening slightly, but still pretty watery.
4. Now reduce the heat to low, and add the finely chopped winter melon candy, ginger powder, salt, lemon zest, vanilla, toasted sesame seeds, and coconut flakes. Mix well. Cook for another 10 minutes, until there is no visible liquid, and turn off the heat.
5. Stir in the toasted glutinous rice flour in a few batches and press everything together using a rubber spatula, until the flour is fully mixed in and you have a thick translucent paste. Cool.
6. After cooling, weigh the filling, and divide it evenly into 10 equal portions. Roll the portions between your palms into balls.

Make the water and oil doughs & combine them:

1. To make the water dough, add the flour to a mixing bowl, and use a pastry cutter or two butter knives to cut the lard into the flour. Mix in the water to form a dough. Roll into a ball, cover (we just cover the bowl with an overturned plate), and let it rest for 15 minutes.
2. To make the oil dough, add the flour to a mixing bowl, and cut in the lard with a pastry cutter or two butter knives. Mix with your hands into a dough, and roll it into a ball. Cover, and let it rest for 15 minutes.
3. Next, combine the two doughs. After both have rested for 15 minutes, roll out the water dough ball into a round disc large enough to evenly wrap around the oil dough ball. Place the oil dough ball in the middle, and bring the water dough up around it, sealing all seams tightly closed.
4. Place the ball of two doughs seam-side down on your work surface. Flatten the ball, and use a lightly floured rolling pin to roll it out into an 8x12 inch (20x30cm) rectangular sheet. Roll up the short end of the sheet tightly into a roll. Cover and refrigerate for 30-60 minutes to chill. (You can chill for less time in colder weather, or if your kitchen is very warm, chill for the full 1 hour.)
5. Next, roll out the refrigerated dough roll into a 10x14 inch (25x35cm) rectangular sheet. Then roll up the short end again into a 10-inch (25cm) long roll, making sure it is a relatively even thickness everywhere. Use a ruler to cut this roll into 10 roughly equal pieces.

Assemble & Bake:

1. Take one dough segment, and stand it upright so that the swirls are facing up. Use your palm to press it flat. With a rolling pin, roll the dough into a 4-inch disc that is slightly thinner around the outer edges, and thicker in the middle.
2. Add a ball of winter melon filling to the center, then close the dough around it until it’s sealed tight without air pockets or visible filling. Place it seam side down, gently flattening the ball into a round disc that’s ½-inch (1.25cm) thick.
3. Place seam-side down on a parchment-lined baking sheet. Repeat until you’ve made all the wife cakes, placing them on the baking sheet about 1 inch apart.
4. With a rack positioned in the middle of the oven, preheat the oven to 400°F/200°C on a convection setting/in a fan-assisted oven, or to 425°F/220°C in a conventional oven with a regular bake setting.
5. Use a sharp knife to cut 2 to 3 slashes into the top of each wife cake to release steam during baking. Mix the egg yolk with the water, and brush the tops of the wife cakes with egg wash.
6. Bake the wife cakes for 20-22 minutes with convection/fan or 25-30 minutes at a regular bake setting until lightly golden brown on top. Baking them a couple of minutes over is fine—just make sure to bake until the tops are lightly golden brown.
7. Cool completely on a cooling rack before serving. Wife cakes taste the best at room temperature. You can refrigerate any leftovers that are more than 3 days old, but let them come back up to room temperature before serving. Enjoy!