-butter -oil -sugar -eggs -vanilla -flour -cocoa powder -Oreos -baking powder -baking soda -cream of tartar -powdered sugar -heavy cream
Preheat oven to 350 degrees Fahrenheit. Line a cookie sheet with parchment paper and set aside. Finely chop 2 cups of Oreos, set aside. In the bowl of a stand mixer, cream together butter, oil, and sugar.
Add eggs and vanilla and mix until creamy. In a medium mixing bowl, combine flour, black cocoa powder, crushed Oreos, baking soda, baking powder. Whisk dry ingredients together. Add half of the dry ingredients to the wet ingredients and mix well. Scrap down the sides of the bowl. Add the remaining dry ingredients, and mix thoroughly.
Using a large cookie scoop, scoop dough into equally sized cookie dough balls. Place cookies evenly on the prepared cooking sheet. Press the cookie flat using the bottom of a glass or measuring cup. Bake the cookies for 10 minutes, don’t overbake.
Allow cookies to cool completely before frosting. While the cookies are cooling, make the frosting. To make the frosting: In the bowl of a stand mixer combine butter, powdered sugar, heavy cream, and vanilla. Mix until well combined, stopping to scrape down the sides of the bowl. Using a Ziploc bag with the corner cut off or a piping bag fitted with a small round tip, pipe frosting on top of cookies in a circular motion.