Prepare the Filling: In a medium bowl, beat softened cream cheese with powdered sugar and vanilla extract until smooth. Gently fold in the finely diced fresh strawberries. Cover and refrigerate for at least 30 minutes to firm up.

Make the Mochi Dough: In a large heatproof bowl, whisk together glutinous rice flour, wheat starch, powdered sugar, and milk until smooth. Stir in the vegetable oil. Cover the bowl with plastic wrap, poking a few holes for steam to escape.

Steam the Mochi: Steam the mochi mixture over high heat for 15-20 minutes, or until it turns translucent and no longer sticky. Stir the dough every 5-7 minutes during steaming to ensure even cooking.

Cool the Dough: Once steamed, remove the bowl from the steamer. Carefully scrape the hot mochi dough onto a clean, cornstarch-dusted surface. Allow it to cool slightly until it's comfortable to handle.

Assemble the Mooncakes: Divide the chilled strawberry cream cheese filling into 8-10 equal portions (about 30g each) and roll them into balls. Divide the mochi dough into 8-10 equal portions (about 40g each).

Form the Mooncakes: Flatten one piece of mochi dough into a circle (about 3-4 inches in diameter) using your hands, lightly dusted with cornstarch. Place a filling ball in the center. Carefully gather the edges of the mochi dough around the filling and pinch to seal, forming a smooth ball.

Shape with a Mooncake Mold: Lightly dust a mooncake mold with cornstarch. Place the mochi ball (seam-side up) into the mold and gently press down to form the desired mooncake shape. Carefully push out the mooncake. Repeat with remaining dough and filling.

Chill and Serve: Arrange the finished mochi snow skin mooncakes on a plate. Cover loosely with plastic wrap and refrigerate for at least 1-2 hours before serving. Enjoy fresh!