Prepare the Brownie Batter:

Preheat oven to 350°F (175°C). Line a 9×9-inch baking pan with parchment paper and lightly grease it.

In a large bowl, whisk together melted butter, granulated sugar, and brown sugar until smooth.

Add eggs, vanilla extract, and blue food coloring, mixing until well combined.

Sift in flour, cocoa powder, baking powder, and salt. Fold gently until just combined. Do not overmix.

Fold in chopped Oreos, reserving a few for the top.

Make the Cream Cheese Swirl (Optional):

In a small bowl, mix cream cheese, powdered sugar, and vanilla extract until smooth.

Drop spoonfuls of the cream cheese mixture over the brownie batter and use a knife to swirl it in.

Bake the Brownies:

Pour the batter into the prepared pan and spread evenly.

Sprinkle reserved Oreo pieces on top.

Bake for 30-35 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs.

Let the brownies cool in the pan for 15 minutes, then transfer to a wire rack to cool completely before slicing.