Preheat the oven to 350° F and line an 8×8 inch pan with parchment paper or spray with nonstick baking spray.

In a microwave safe bowl combine the 1/2 cup butter and 6 oz chocolate. Microwave for 30 seconds at a time stirring in between until the chocolate is completely melted. Up to 90 seconds total. Let the chocolate cool for a couple minutes.

In a medium bowl add the 1 cup sugar and 3 large eggs and whip on high speed using an electric mixer for 4 minutes. You can use a hand mixer or a stand mixer fitted with the whisk attachment.

Gently fold the chocolate and butter mixture into the eggs taking care not to deflate the eggs. Use a spatula for this and don’t mix vigorously. Add the 1 tsp vanilla extract and mix.

Next add in the 1/2 cup flour, 1/4 cup cocoa powder, and 1/2 tsp kosher salt. Mix gently until combined.

Pour half of the batter into the lined baking pan, then line the pan with 16 Oreo cookies. Pour the rest of the brownie batter on top.