Preheat the oven to 350F then line a baking sheet with parchement paper and set aside.
In a food processor, grind the 8 Oreos until finely crushed. In a medium bowl, mix the crushed Oreos, flour, cornstarch, cocoa powder, baking soda, baking powder, and salt then set aside.
8 oreo cookies, 1 & ⅓ cup flour, 3 tablespoon corn starch, ¼ cup black cocoa, ½ teaspoon baking soda, ½ teaspoon baking powder, ¼ teaspoon salt
In a stand mixer bowl, cream the softened butter, brown sugar, and granulated sugar until light and creamy.
½ cup butter, ¼ cup granulated sugar, ½ cup light brown sugar
Add in the egg and the vanilla and mix again until combined. Scrape the bowl when needed.
1 large egg, 1 teaspoon vanilla extract
Add in the dry mixture and mix until the dry mixture disappears then fold in the chocolate chips and the chopped-up Oreos. Then using a large cookie scoop, scoop out 8 equally sized cookie dough balls, place on a baking sheet and flatten to about ¾ inches in thickness, and bake the cookies for 9 minutes. Make sure not to flatten them too much so they don't come out super thin. ⅔ cup white chocolate chips, 3 Oreos
As soon as the cookies come out of the oven top with extra Oreo pieces and white chocolate chips. Allow them to cool down on the baking sheet for 10 minutes before transferring to a cooling rack. Enjoy with a tall glass of milk.