Dry fry kuachi (melon seeds) over medium heat for about 3 to 5 minutes. Remove and allow it to cool.
Mix into lotus seed paste. Form into 10 balls measuring slightly approximately 1.5 oz (45g) each.
Divide black sesame paste into 10 portions of 2.5 oz (70g) each. Wrap each portion of black sesame seed paste over each portion of lotus seed paste forming 10 balls of filling.
Sift cake flour into a large bowl. Make a well in the center. Combine maple syrup, vegetable oil, and alkaline water in a small bowl or measuring cup. Pour syrup mixture into well and mix with a spatula to form a soft dough. Cover and let it rest for 30 minutes.
Lightly dust working surface with cake flour. Knead dough until smooth adding a little flour if necessary. Divide into 10 portions of 45g each.
Take a portion of the dough and spread it into a circle of about 4 inches (10cm). Wrap a ball of filling with the dough.
Roll the ball of dough and filling between your two palms to smoothen. Place into a flour dusted mooncake mold.
Flatten dough to conform to the shape of the mold. Place on your working surface and carefully press spring stamp down to get a nice pattern on the top.
Lift mold and gently release mooncake onto your palm.
Place on a parchment lined baking tray. Repeat with the remaining dough and filling.
Bake in a preheated 375°F (190°C) oven for 10 minutes. Remove from oven and allow mooncakes to cool for 5 minutes. Brush on egg wash and return to oven for another 8 to 10 minutes.
Remove from oven and brush on some mooncake glaze just on the top of mooncakes.
Place on a wire rack to cool completely. Store in an airtight container for one to two days before serving.