You'll Need: 9x9 Pan Nonstick Foil Reese's Peanut Butter Topping Peanut Butter Oreo Gooey Bars Ingredients 1/3 cup unsweetened cocoa powder 1/2 teaspoon baking soda 1/4 teaspoon salt 1 1/4 cups flour 1/2 cup butter, softened 2/3 cup light brown sugar 1/4 cup sugar 1 teaspoon vanilla 1 large egg 18 Oreo cookies, chopped 1/2