How to Make It
Preheat oven to 350 degrees
In a medium sauce pan, melt 10 tbsp butter over medium-high heat. Add the 3/4 cup cocoa powder and 1 1/4 cups sugar. Whisk to combine and remove from heat. Add the 1/2 tsp salt, 2 tsp vanilla and 2 eggs and whisk until fully combined. Mix in 1/2 cup of flour. Set batter aside.
Cookie dough layer:
With an electric mixer, cream together the butter and sugars. 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 fully incorporated. Fold in the chocolate chips. Set dough aside.
Line the bottom of a 9x9 baking pan with tin foil and spray the tin foil with a layer of baking spray.
Layer 1/2 of the cookie dough on the bottom of a 9x9 baking pan, pressing down to form the bottom layer. Reserve the remaining cookie dough to be used to make cookies the next day.
Layer as many Oreos that will fit over top of the cookie dough. Don't overlap. One single layer will do.
Pour the brownie batter on top of the Oreo layer and spread until evenly layered on top.
Bake for 30-35 minutes, or until a toothpick inserted into the center comes out clean. Let the brownies cool before serving. Serve with ice cream.