If making red bean paste from scratch, soak red beans overnight, drain, and boil until very soft. Mash or blend, then cook with sugar and oil until thick. Let cool completely.

Divide red bean paste into 6-8 equal portions (approx. 25-30g each) and roll into balls.

Combine glutinous rice flour, cornstarch, and powdered sugar in a bowl. Gradually whisk in milk until smooth.

Add vegetable oil and mix well.

Strain the mixture into a heatproof bowl to remove any lumps.

Steam the mixture over high heat for 20-25 minutes, stirring every 5-7 minutes, until it forms a translucent, sticky dough.

Let the dough cool slightly until it's comfortable to handle.

Lightly dust your work surface and hands with cooked glutinous rice flour (or cornstarch) to prevent sticking.

Divide the cooled dough into 6-8 equal portions (approx. 35-40g each). Flatten each portion into a disc.

Place a red bean paste ball in the center of each dough disc. Carefully wrap the dough around the filling, sealing completely.

Press the filled ball into a mooncake mold. Gently press down and then release to form the patterned mooncake.

Repeat with remaining dough and filling.

Chill the mooncakes in the refrigerator for at least 2 hours before serving.

Store leftover mooncakes in an airtight container in the refrigerator for up to 3-4 days.