01 - Preheat oven to 350°F. Line a baking tray with parchment paper.
02 - In a bowl, combine golden syrup, vegetable oil, and alkaline water. Stir until smooth and well incorporated.
03 - Add flour to the wet ingredients and mix into a soft dough. Cover and let rest for 30 minutes at room temperature.
04 - Divide lotus seed paste into 12 equal portions (about 1.5 oz each). If using salted egg yolks, place one yolk in the center of each paste ball and shape into a smooth sphere, completely enclosing the yolk.
05 - Divide rested dough into 12 equal pieces (about 0.9 oz each).
06 - Flatten a piece of dough into a disc. Place a filling ball in the center and wrap the dough around it, sealing completely. Repeat for all portions, ensuring no filling is visible.
07 - Lightly dust each ball with flour. Place into a floured mooncake mold and press firmly to imprint the pattern. Invert to release onto the baking tray.
08 - Bake for 5 minutes, then remove from oven and let cool for 10 minutes.
09 - Whisk egg yolk and water for the glaze until smooth. Brush a thin, even layer over the top and sides of each mooncake.
10 - Return mooncakes to the oven and bake for an additional 15-20 minutes, or until golden brown.
11 - Cool completely on a wire rack. Store in an airtight container for 1-2 days to allow the skin to soften and develop the traditional texture before serving.