Thin Mint Brownies

Thin Mint Brownies

Nobody said sheet cakes have to be boring! 

Sometimes I need a dessert that’s simple and goes together quickly! A decorated 9x13 sheet pan of cake or brownies can easily be made from scratch OR doctored-up mixes, and they’re easy to decorate, festive, delicious, and can serve a large crowd!

It’s Girl Scout cookie season, and I got several boxes of cookies recently from my nieces – including two boxes of Thin Mints! I needed a way to get them out of the house before I ate both of them by myself….so onto a pan of brownies they went! HUGE hit when I took them to work; they were gone soo fast!
Recipe(s) below!

2 quick recipe notes - 

First – you have lots of options here!
I'm a dense-chocolatey-brownie addict, and the recipe below reflects that! These brownies will be very much on the rich side, especially with the cream cheese frosting added. If you'd rather have a slightly-less-dense dessert I'd use a chocolate sheet cake recipe like this one!

Second - time-saver options!
If you’d rather doctor up brownie mixes, use two mixes (I usually go with Ghiradelli), substitute butter for the oil, replace the water with milk or buttermilk, and add an extra egg!)

"What if I don't have Thin Mints?" 

I know...they're not available year-round. I kinda wish that was different! There are similar cookies available online - I've linked them below - or you can use any other chocolate mint cookie or After Eights or Andes mints. 

One more option - Oreo brownies! 

I've made a similar dessert substituting Oreos for the Thin Mints - leave the mint out of the brownie layer, but add 1 cup of chopped Oreos. You can also substitute dark or black cocoa powder and make a darker brownie layer to resemble the Oreo cookie a bit more! 

(Disclosure: As an Amazon associate I may earn from qualifying purchases, and my posts often contain affiliate links. If you click a link and make a purchase, I may receive a commission at no extra cost to you!) 

Oreo Brownies
Oreo Brownies

Thin Mint Brownies

Who said sheet cakes have to be boring? These Thin Mint Brownies are covered with cream cheese buttercream frosting and Thin Mint cookies!
Prep Time20 minutes
Cook Time40 minutes
Decorating time15 minutes
Total Time1 hour 15 minutes
Course: Dessert
Cuisine: American
Keyword: Brownies with Cream Cheese frosting, Brownies with Thin Mints, Cream Cheese Frosted Brownies, Thin Mint Brownies
Servings: 24 servings
Calories: 437kcal




Mint Cream Cheese Frosting

  • 8 ounces cream cheese (one package; softened)
  • 1 cup butter (two sticks, softened)
  • 6 cups powdered sugar
  • 1-2 Tablespoons milk
  • 1 Tablespoon mint extract (I used McCormick’s Mint extract)
  • 1/4 teaspoon salt (if using unsalted butter)
  • 1-2 drops green gel food color (save and add later - I colored about ½ cup of the frosting a deep green, added a tiny drop to another cup of frosting to make a mint green, and left the rest white.)


  • 15-20 Thin Mint cookies
  • Sprinkle mix of your choice! optional; I used 'Silver Bells' by FancySprinkles



  • Preheat oven to 350°F. Grease a 9x13 baking pan with non-stick or baker’s floured cooking spray.
  • Mix together melted butter and granulated and brown sugars. Whisk in eggs until well combined. Whisk in cocoa powder, baking powder, salt, and gradually stir in all-purpose flour until combined. Stir in vanilla, mint extract, and chocolate chips, and pour into prepared pan.
  • Bake for 35-40 minutes (or until a toothpick comes out clean). Cool completely before frosting. Set in the fridge or freezer to accelerate the cooling process if desired. (This is a great time to make your frosting!)

Mint Cream Cheese Frosting

  • Beat together softened cream cheese and butter; slowly add in powdered sugar alternating with milk and mint extract until frosting reaches a pipeable consistency. Add salt if needed and beat until well combined.


  • Color frosting to your liking - I transferred about 1/2 cup to a small bowl and 1 cup to a slightly larger bowl, and colored them dark and light green. The rest I left white!
  • Transfer frosting(s) to piping bags – I used the large open star from my large tip set and a smaller open star and oblong teardrop-shaped tip from my smaller set when I piping on the frosting. I usually find it easiest to start with the larger tips and fill in around them with smaller designs. Up to you!
  • Add sprinkles to your liking – I started with larger ones spaced where I thought they looked best and then added smaller ones in between them.
  • You could also skip the ‘placement’ and just sprinkle them over the top! The first method might give you a more polished look, but the second's usually more fun!
  • Annnd you’re done! High-five yourself –and enjoy!



(Please note nutrition information is an estimate, and may not be exactly accurate. Counts will be lower in all fields if full batch of frosting is not used.) 


Serving: 1serving | Calories: 437kcal | Carbohydrates: 58g | Protein: 4g | Fat: 22g

Mentioned in post -
Cream Cheese Buttercream Frosting

Did you make these Thin Mint Brownies? 

Let me know how it went - or find me on Pinterest or on Instagram and tag @IntensiveCakeUnit in your photo!

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