The Ultimate Peanut Butter Cookie Cake

For those of you that know me, or frequently follow the recipes posted here on Life Made Simple, you know I’m kind of obsessed with peanut butter! I’ll take it any form, but today it’s a cookie cake! Being almost 9 months pregnant, I’ve been trying to scale down the amount of time I spend in the kitchen. Sad, I know, but with some dislocated ribs it’s been hard to bend over and prep and wash dishes. So I’ve been simplifying meals and baking treats that require minimal work. Although cookies aren’t the most difficult or time consuming thing to make, I wanted to whip up something that I could just pop in the oven and forget about for a few minutes.
I decided to make a peanut butter version of this M&M Chocolate Chip Cookie Cake that I made for Stephen’s birthday last year. I mixed in a handful of peanuts, peanut butter M&Ms, peanut butter chips and of course, peanut butter! It baked up perfectly in my Wilton cookie cake pan and I topped it with some peanut butter frosting once it had cooled.
It was a fun and easy treat to make that was perfect just for the two of us to snack on, but would be great for birthdays or parties too! If you are a fan of peanut butter, this ultimate peanut butter cookie cake is for you! Enjoy!

The Ultimate Peanut Butter Cookie Cake
Prep time
Cook time
Total time
A giant peanut butter cookie filled with M&Ms, peanut butter chips and peanuts. Baked in a cookie cake pan, it's the perfect treat for any celebration!
Yield: 8
  • 1½ c. all-purpose flour
  • ¾ c. sugar
  • ½ c. brown sugar
  • 1 c. creamy peanut butter
  • ½ c. butter, room temperature
  • 2 eggs
  • 2 tbsp. heavy cream milk
  • ¾ tsp. baking soda
  • ½ tsp. baking powder
  • ¼ tsp. salt
  • 1 tsp. vanilla extract
  • ½ c. peanut butter M&M's or peanut butter cups, coarsely chopped
  • ½ c. peanut butter chips
  • ½ c. dry roasted peanuts, coarsely chopped

  • Creamy Peanut Butter Frosting:
  • 1 c. powdered sugar
  • 8 tbsp. (1 stick) butter, room temperature
  • ¼ c. creamy peanut butter
  • 1 tbsp. heavy cream
  • pinch of salt
  1. Preheat oven to 350 degrees. Line one giant (11") cookie pan with parchment paper, set aside (I usually just cut out a large circle for the bottom).
  2. In the bowl of a stand mixer, beat together sugars, butter and peanut butter until smooth, about 2-3 minutes. With mixing speed on low, add vanilla, heavy cream and one egg. Mix until incorporated, then add remaining egg.
  3. In a medium size mixing bowl, whisk together flour, baking soda, baking powder and salt. With mixing speed on low, gradually add dry ingredients, mixing until no visible dry ingredients remain. Remove bowl from stand and gently fold in M&M's (or peanut butter cups), peanut butter chips and chopped peanuts.
  4. Using a spatula, place the dough into the pan, pressing to create an even layer. Place the pan in oven and bake for 16-20 minutes or until the edges become golden brown in color. Remove from the oven and allow to cool for 45 minutes before frosting.
  5. Meanwhile, to prepare the frosting, beat all ingredients together for 3 minutes or until mixture becomes light and fluffy. Place into a piping bag with desired tip and pipe onto the cooled cookie, around the edges or in the center if you want to write something on it.
-Makes 1 (11") cookie cake. It can also be baked in an 8x8" square pan for extra thick bars or a 9x13" pan for thinner bars.

Recipe source: adapted from Smitten Kitchen, Peanut Butter Cookies


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About the Author


Wife, mother, baker and photographer. Recipe developer & author of Life Made Simple. A self-professed peanut butter lover and fond of anything that involves pumpkin, cookie dough, or sprinkles

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