This Oreo Cookie Cake is rich, chewy, and so delicious. A giant cookie stuffed with Oreos and topped with an Oreo buttercream that will knock your socks off!
Preheat the oven to 350 degrees Fahrenheit. Line the bottom of a 9-inch round springform pan with parchment paper that has been cut in a circle to fit.
Whisk the flour, cornstarch, baking soda, and salt together in a medium bowl until combined.
In a separate large bowl, beat 3/4 cup room temperature butter until smooth using an electric mixer.