Preheat oven to 350º F, Prepare an 8 inch baking pan by lining with parchment paper or spray with non-stick spray.
Is a mixing bowl whisk together melted butter with brown sugar and granulated sugar until smooth and no lumps. Beat in egg, egg yolk and vanilla until the egg is fully incorporated.
Stir in the flour, salt, and baking powder. Mix until the white streaks just disappear.
Fold in the white chocolate chips until evenly incorporated.
Spread about 1/2 of the batter into your prepared pan. Arrange the 12 Golden Oreos over the batter (3 rows of 4). Top with the remaining batter.
Bake for 25-30 minutes, a tester inserted should come out clean.