In a heatproof bowl, combine glutinous rice flour, wheat starch, powdered sugar, water, milk, and vegetable oil. Whisk until smooth and no lumps remain.

Cover the bowl with plastic wrap and steam over high heat for 20-25 minutes, or until the dough is cooked through and translucent.

Once cooked, carefully remove the dough from the steamer. While still warm, knead it with a spatula or gloved hands until smooth and elastic. Let it cool completely.

Divide the lotus seed paste into 25g portions and roll them into small balls.

Once the snow skin dough is cool, divide it into 30g portions and roll them into balls. Lightly dust your work surface and hands with cooked glutinous rice flour (kao fen) to prevent sticking.

Flatten a piece of snow skin dough into a thin circle, slightly larger than the filling ball. Place a lotus paste ball in the center.

Carefully bring the edges of the dough up and around the filling, sealing it completely. Roll gently between your palms to form a smooth ball.

Lightly dust a mooncake mold with kao fen and tap out any excess. Place the filled dough ball into the mold.

Press the plunger firmly down to imprint the pattern, then gently release the mooncake from the mold.

Repeat with the remaining dough and filling. Arrange mooncakes on a plate, cover loosely with plastic wrap, and refrigerate for at least 2 hours before serving.