Mix unsalted butter, sugar, brown sugar, and salt in a bowl using a hand mixer.

Add the egg and vanilla extract gradually in three parts, mixing well after each addition.

Sift together all-purpose flour, baking powder, matcha powder, and corn starch, then mix into the wet ingredients.

Fold in the white chocolate chips and divide the dough into six equal portions.

Wrap each portion of dough around 20g of cream cheese to form a ball.

Chill the dough balls in the refrigerator for 30 minutes to 1 hour.