Preheat oven to 350 degrees F. Line a 9×5 inch metal loaf pan with foil and spray the foil with cooking spray.Cream the butter with the brown and granulated sugar. Beat in the vanilla and egg and beat just until the egg is mixed, then beat in the salt and baking soda. By hand, stir in the flour until it is incorporated. Stir in the chocolate chips. Press about HALF of the dough into the bottom of the pan as evenly as possible (freeze the rest). Press 8 whole Oreos directly into the dough, spacing evenly. Detach one side of each of 8 berry flavored (or other flavor) Oreos, and stick the Oreo “missing side down” on top of the other Oreos so that you have 8 little stacks.Wash out the mixing bowl. Melt the butter in the mixing bowl (if using a microwave-safe bowl) or just melt the butter and add it to the bowl. Stir in the cocoa powder until smooth. Stir in the sugar and vanilla.
Add the egg and whisk lightly (do not beat) just to blend, then whisk in the salt, and baking powder.
Add the flour and stir until it is incorporated.
Pour over the Oreos and spread batter to cover them.
Bake on the center rack at 350 for 30 minutes or until brownies appear set and edges are puffed up. Cool on a wire rack. When cool, chill the brownies for about 2 or 3 hours. Lift from pan and cut into 16 squares.
