Pre-heat the oven to 350 degrees.
Line the bottom of the baking pan with tin foil and leave a 2-3” overhang on both sides. Spray the tin foil with Pam.
In a large sauce pan, melt the butter over medium high heat. Add the sugar and cocoa powder once the butter is melted. Whisk to combine and remove from heat. Add the salt, vanilla and eggs and continuously whisk until the eggs are combined. Add the flour and continue to mix. Set batter aside.
Cream together the butter and sugars in a mixer. Add the eggs and vanilla, making sure to scrape down the sides of the mixing bowl. Add the flour, salt, baking soda and baking powder and mix on low until everything is incorporated. Fold in the chocolate chips. Set dough aside.
Layer the cookie dough on the bottom of a 10×15 baking pan, pressing down to form the bottom of the slutty brownies. Put as many Oreos as will fit in a single layer on top of the cookie dough.
Pour the brownie batter on top of the Oreo layer and make sure it’s evenly layered on top.
For a 10×15 pan, bake for 45-50 minutes. For a 9×13 pan, add about five minutes. Test with a knife to see if the center is done. If the knife comes out clean, let the brownies rest before serving. If the knife comes out with batter still on it, allow the brownies to bake about 5 more minutes.