In a large bowl, combine the glutinous rice flour, cornstarch, cocoa powder, white sugar, corn oil, and milk until you have a smooth, lump-free mixture.

Sift the batter through a fine sieve to ensure a velvety texture, then pour it into a pot.

Place the pot over low heat and stir constantly until the mixture thickens into a dough that no longer sticks to the sides of the pot.

Once the dough is formed, turn off the heat and allow it to cool enough to handle.

Stretch and pull the dough repeatedly until it becomes smooth and stretchy.

Roll small portions of the dough into bite-sized balls and smooth them out.

Coat each mochi ball in crushed Oreo cookies, ensuring they are fully covered.