Oreo Crumbl Cookie Dupe

In a large bowl, cream butter, granulated sugar, and brown sugar until light and fluffy, about 2–3 minutes. Add eggs and vanilla, mixing well. In a separate bowl, whisk together flour, black cocoa powder, cornstarch, baking powder, baking soda, salt, and Oreo crumbs. Mix dry ingredients into wet ingredients just until combined. Fold in chopped Oreos if using. Do not overmix. Chill dough for at least 30 minutes. Scoop dough balls and gently shape into thick discs, do not flatten too much. Place on baking sheet. Bake at 350°F for 9-12 minutes. Cookies should look slightly underbaked in the center but set around the edges. Cool on the pan for 10 minutes, then transfer to a rack to cool completely before frosting. To make frosting: In a large bowl, beat the unsalted butter and cream cheese until light and creamy. Add in the powdered sugar. Beat until creamy. Pipe or spread frosting on top of the cooled cookies! Store in an airtight container in the refrigerator for 3-4 days.