Knead all the water-oil crust ingredients in a bread machine (or by hand) until smooth.
Knead until the dough is elastic and stretches into a thin membrane. A full windowpane is optional with corn oil.
Put the cake flour and corn oil for the oil dough in a large container.
Mix the oil dough with a spatula until completely smooth; do not knead.
Wrap both doughs in plastic and chill in the fridge for 40 minutes.
Spray the salted egg yolks with baijiu, roast at 355°F (180°C) for about 8 minutes, then crush into crumbs.
Measure out the sweet white bean paste.
Mix the crushed yolks into the bean paste until smooth and even.
Divide the filling into 12 balls, then chill for 30 minutes.
Press the water-oil dough flat, wrap a portion of oil dough in the center, and seal by pushing the edges up and over.
Press the wrapped ball into an oval, roll it out evenly from the center, and roll it up into a tight scroll.
Cover all the rolls and chill for 20 minutes.
Repeat the lengthen-and-roll technique a second time on each piece.
Cover and rest the second rolls at room temperature for 15 to 20 minutes.
Press the center, fold the ends in, flip, roll out, fill with the yolk-bean ball, and seal, keeping the textured side out.
Leave the surface irregular; this is the signature Huangzhuang look.
Poke small holes in the tops with a skewer and add a little corn oil to the baking sheet.
Bake at 355°F (180°C) with both heats for 13 minutes.
Flip the mooncakes, keeping the empty oven running.
Return to the oven and bake 13 more minutes at 355°F (180°C). Adjust for your own oven.
Cool the baked mooncakes on the sheet.
Break one open to check the fine, flaky layers.
Enjoy the crumbly, golden mooncakes.
Serve at room temperature over a plate, because they crumble gloriously.