This giant format cookie is decorated with a chocolate peanut butter buttercream frosting and a smattering of cheerful peanut butter candy. With a caramelized, crispy edge and a soft, almost gooey interior, this salty-sweet masterpiece is the stuff of childhood dreams.
Preheat the oven to 350F. Grease a 9" cake pan with non-stick spray, then line the bottom with a round of parchment. Set aside.
Start by creaming the butter, peanut butter and sugars together until light and fluffy. Don't rush this step! The sugars create pockets of air in the butter for a lighter texture and finer crumb.Add the eggs and vanilla, scraping down the sides. Mix until incorporated.Add the dry ingredients in stages, mixing until just uniform. Using a spatula or wooden spoon, mix in about ¾ of the chocolate chips, nuts and candy.
Put the dough into your prepared pan, smoothing the top down using your hands, the back of a spoon or the flat bottom of a drinking glass. Sprinkle the remaining chips/nuts/candy across the top, then pop the tin into the preheated oven. Bake for 23-25 minutes, or until golden brown with the center mostly set.Remove the cookie cake to a cooling rack. Allow to cool for about 15 minutes before removing from the tin. Cool to room temperature before attempting to frost.
Start by beating the butter and peanut butter together until light and fluffy. Sift in the cacao and powdered sugar to prevent lumps. Add the salt and vanilla. Mix to combine.Working about a tablespoon at a time, add the milk to the frosting until you reach the right consistency. It should hold its shape, but be thin enough to pipe.
Feel free to get as wild and crazy with the design as you like. I opted for simple rosettes around the edge and a larger one in the center because my piping skills are still pretty rudimentary. Use chocolate chips, peanut butter chips, roasted peanuts, and/or peanut butter candies to finish the decoration/cover any mistakes.
Slice into wedges and enjoy!
Notes
Don't have piping bags on hand? Simply snip the corner off of a disposable zip top bag!
Feel free to swap in any other nut or seed butter that you prefer.