Happy end of the week, guys! I’m celebrating with cookies, as I always do. But today it’s these Frosted Peanut Butter Cookie Bars, and man it’s a good Friday!

If you can bake cookies into bar form, I say do it. It’s about a million times faster and easier, and I do it quite a lot to save time. Square cookie, round cookie, I think we can manage with either guys. Let’s get to it!

How to Make Frosted Peanut Butter Cookie Bars

These come together just like a typical cookie dough. The recipe includes powdered sugar in addition to regular sugar, which creates a kind of soft, fluffy cookie texture. We’re starting by whisking together all the dry ingredients and setting that aside.

Then beat together your butter, creamy peanut butter, sugar, and powdered sugar until fluffy. Stir in the egg, water, and vanilla extract (Origin Vanilla is my preferred brand!), and then it’s time to add the dry ingredients and beat until you’ve got a thick dough. Spread it in your prepared baking pan evenly- it will look something like this:

And then bake it up! The frosting is a simple peanut butter American buttercream, and it comes together quickly, so spread it all over the baked and cooled cookies. Then it’s just time to slice and enjoy guys!

Sometimes I really just don’t have the patience to bake cookies in batches, and this is a great recipe to bake up in a 9×13 cake pan in just one batch. I’m just sayin, you could have a whole pan of cookies in like 45 minutes guys.

Tips & Troubleshooting For Your Peanut Butter Cookies

This recipe is super simple, but here’s a couple of tips for baking this recipe!

Use a well greased 9×13 inch baking pan. This is a pretty standard cake pan, and you really need this size to get the right thickness and baking time here. Alternatively, you can scoop and bake these into classic cookies at the same temp, and bake them for about 8 minutes, or until lightly golden brown.

Why is there water in this recipe? High-altitude baking can be tricky, and one important thing that occurs at high-altitude is that water evaporates more quickly. Adding a little bit of water to the cookie dough not only helps the dough become easier to spread, but it helps retain that fluffy texture when baking!

Can I freeze these cookies? These cookies can be frozen, but I recommend freezing them without the frosting as it can produce condensation when thawed. Wrap the cookies tightly in an air-tight container, and they can be frozen for 2-3 months and thawed on the counter to enjoy! You can also freeze the dough before baking, but be sure to thaw completely for several hours to room temp before baking.

What if my frosting breaks? American buttercream is fairly easy to fix, and if your frosting is broken it is likely because your ingredients were not all at room temp. You can pop the whole bowl in the fridge for a few minutes and then re-whip.


Frosted Peanut Butter Cookie Bars

Servings 12 large cookie bars


For the cookie bars:

  • 3 cups flour
  • 1/2 tsp. salt
  • 1/2 tsp. baking powder
  • 1/8 tsp. baking soda
  • 1/2 cup softened butter
  • 1/3 cup creamy peanut butter
  • 3/4 cup sugar
  • 1/4 cup powdered sugar
  • 1 egg
  • 3 tbs. water
  • 2 tsp. vanilla extract

For the frosting:

  • 1/2 cup softened butter
  • 1/2 cup creamy peanut butter
  • 3 cups powdered sugar
  • 1 tsp. vanilla extract
  • 1/4 tsp. salt
  • 2 tbs. heavy cream


For the cookie bars:

  1. Preheat your oven to 350 degrees, and grease a 9x13 inch pan.
  2. In a medium bowl, whisk together the flour, salt, baking powder, and baking soda. Set aside.
  3. In a large bowl, beat together the butter, peanut butter, sugar, and powdered sugar until fluffy. Beat in the egg, water, and vanilla extract.
  4. Slowly add in the flour mixture, and stir until completely combined.
  5. Spread the dough evenly in your prepared pan. Bake for 14-16 minutes, or until the cookies look just golden near the edges. Cool completely before frosting.

For the frosting:

  1. In a medium bowl, beat together the butter, peanut butter, powdered sugar, vanilla extract, and salt until combined and thick.

  2. Beat in the heavy cream until the mixture becomes fluffy.
  3. Spread over the cooled bars evenly. Enjoy!


  1. Kevin Mack

    October 8, 2020 at 6:34 am

    You forgot to add the peanut butter in your frosting procedure for peanut butter frosted peanut butter bars?

    • Dough-Eyed

      October 8, 2020 at 2:54 pm

      Hi Kevin! Sorry about that- I've updated the recipe card. You beat it in along with the butter! Thank you!


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