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Our old fashioned Peanut Butter Bars recipe has a thick and chewy base topped a quick chocolate glaze. They're perfect for potlucks or parties and can be made ahead or frozen!
I get more attention for these Peanut Butter Bars than any other cookie bar.
These chewy peanut butter bars are THE treat to bring to every potluck and way better than the Lunch lady peanut butter bars you may remember as a kid. A family friend (thanks Chris McLaws!) shared this recipe with us decades ago and it's been the most popular cookie bar in our family, since. They have the BEST soft and chewy texture and peanut butter flavor and you can double the recipe to bake in a baker's half sheet pan.
How to make Peanut Butter Bars:
Make Dough: With a hand mixer or stand mixer, cream butter, sugar, and brown sugar together. Add eggs, vanilla, and peanut butter then mix again. Stir dry ingredients in separate bowl, then combine.
Bake: Press dough into a greased 9×13″ baking pan and bake at 350°F (180°C) for 17-21 minutes. Be careful not to over-bake! They shouldn't look glossy, but barely set in the center (they will continue to harden as they cool).
Peanut butter and chocolate topping: Cool bars completely then spread a thin layer of peanut butter and melted chocolate glaze on top.
Make Ahead and Freezing Instructions:
To Make Ahead: Peanut butter bars will keep in the refrigerator for up to 1 week. The cookie dough could be made a day ahead of time, stored in the fridge until ready to bake.
To Freeze: Cover homemade peanut butter bars with plastic wrap, then a double layer or aluminum foil and freeze in a freezer safe pan up to 3 months. Thaw overnight in the fridge then bring to room temperature before serving.
More “Bar” Recipes:
- Blondies
- Magic Bars (7 Layer Bars)
- S'mores Bars
- Key Lime Pie Bars
- Ice Cream Sandwiches
- Scotcheroos
- Lemon Bars
- Butterfinger Bars
- M&M Cookie Bars
- Snickerdoodle Bars
- Sugar Cookie Bars
Peanut Butter Bars
Equipment
Ingredients
Peanut Butter Bars:
- 3/4 cup butter, (170g), room temperature
- 1/2 cup granulated sugar, (100g)
- 1 cup light brown sugar, (220g)
- 2 large eggs
- 1 teaspoon vanilla extract
- 1/2 cup creamy peanut butter, (135g), plus more for spreading over baked bars
- 2 1/2 teaspoons baking soda
- 1/2 teaspoon salt
- 1 1/2 cups all-purpose flour, (188g)
- 2 cups old-fashioned rolled oats, (170g)
Chocolate Frosting:
- 1/4 cup butter, (57g)
- 1 Tablespoon unsweetened cocoa powder
- 1 1/2 Tablespoons milk
- 1 1/4 cups powdered sugar, (150g)
- 1 teaspoon vanilla extract
Instructions
- Preheat oven to 350 degrees F.
- Wet ingredients: In a large mixing bowl, cream together the butter, sugar and brown sugar. Add the eggs, vanilla, and peanut butter and mix well.¾ cup butter, ½ cup granulated sugar, 1 cup light brown sugar, 2 large eggs, 1 teaspoon vanilla extract, ½ cup creamy peanut butter
- Dry Ingredients: In a separate bowl mix together the dry ingredients.2 ½ teaspoons baking soda, ½ teaspoon salt, 1 ½ cups all-purpose flour, 2 cups old-fashioned rolled oats
- Combine: Add dry ingredients to creamy mixture. Press firmly into a greased 9×13'' pan.
- Bake at 350 degrees for 17-21 minutes or until no longer glossy, but just barely set in the center. Do not over-bake; they will harden as they cool. Allow to cool completely before frosting.
- Spread Peanut Butter: Once cool, spread a thin layer of creamy peanut butter over the bars.
- Chocolate Frosting: Add butter to a small skillet over medium heat. Once melted, stir in cocoa. Remove from heat and stir im milk, powdered sugar and vanilla. Whisk until smooth, using electric beaters to get out any lumps, if needed. Spread chocolate frosting over the top of the bars.¼ cup butter, 1 Tablespoon unsweetened cocoa powder, 1 ½ Tablespoons milk, 1 ¼ cups powdered sugar, 1 teaspoon vanilla extract
Notes
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
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I originally shared this recipe in April 2013. Updated February 2018, May 2021 (frosting recipe amended), June 2023 and March 2025
Found this a few weeks ago and they are easy to made and delicious. I am about to make my third batch lol —- all the family loved them and we are in Argentina and peanut butter is not popular or used much, so to begin I had to make my own peanut butter. ( very easy too) I adapted the recipe the 2nd time I made them adding crushed nuts in the batter as well as chocolate chips. I also added crushed nuts atop the layer of peanut butter on the top and instead of the icing I simply used melted semi- sweet chocolate. They were a hit and I’ll make them this way again tomorrow adding a bit of coconut on top of the nuts before adding the melted chocolate — lol I want it all! Thanks so much for your recipe …
I made these tonight for our sons and visiting nephews, and they were a huge hit! The chewy texture and delicious flavors were an irresistible combination! I made a favorite topping instead of the recipe’s frosting because of the mixed reviews. Glad I did because it really complimented the bars, is quick and easy, & can’t fail: 1 c. chocolate chips, 1/2 c. butterscotch chips, and 2/3 c. peanut butter melted together, and spread on top of cooled bars! Home Run! Will definitely make these again!
So happy to hear it! Thanks for your comment.
Let me preface by saying that I’m NOT an avid baker. I have probably baked a total of 8 times in my entire life.
Still, this recipe was easy enough for even a novice to follow, and has enough detail to make you feel like a pro (sort of).
Everyone loved them! Consistency and flavour are remarkable. I only had about half the amount of rolled oats in the cupboard, but they still turned out great.
I drizzled the frosting, since I was confident that my attempt to make the frosting smooth and even would turn out poorly. As such, bites that don’t have much chocolate drizzle would not be as sweet, but are still delicious. I have a very sweet tooth, so I was the only one who cared about this. If I drizzle the frosting again next time (yes, will definitely make these again), thinking maybe to put half the confectioners sugar into the dough, and half into the frosting for a more even distrivution. Unless that would be uncouth? ?
Five stars all the way, this recipe is one for the books!
Delicious and chewy!
When making the icing, my butter cake separated during the cooking process and I thought it was botched, but I just powered on ahead and added the icing sugar and everything turned out wonderfully!
Just put icing on ..looks delicious ???
The squares turned out delicious ???
My son and I made these last night and after I cooled and added peanutbutter and chocolate, I cut into them and wanted to try one. It didn’t look 100% done in the middle is that how it’s supposed to be? I baked for 17 first and then let it bake another 3 minutes.
It shouldn’t be doughy in the middle at all–just chewy like a cookie bar.
Everything about these bars are……PERFECT!!! They are the tastiest, chewiest oatmeal bars I have ever had! Might I add the frosting is SO DELISH! Your instructions were easy to follow and I had all the ingredients on hand!! This one is going in the cookbook! Thank you for sharing!
I’m so happy to hear it! Thanks Amber <3
Thank you for notes to prevent over baking … I resisted the urge to bake longer because it appeared to need a few more minutes … So glad I followed your directions !!!
Now waiting for cooling and final steps … Yum … … 🙂
My family loved these bars – they really are addicting! I made them like the recipe said, but didn’t see any reason to boil the milk for 2 minutes. I took it off the heat as soon as it started boiling (making sure I had whisked the cocoa powder in) stirred in the powdered sugar and it was perfect. Will make again!
The recipe for the chocolate icing is incorrect. I wasted the last bag of my powdered sugar trying to make this icing. I think you screwed up and did not include the milk. I ended with lumps in the bottom of the pan.
I’m so sorry it didn’t work for you–something must have gone wrong in the process. I make it with success all the time 🙂
Delicious flavor! Loved the peanut butter and oat combo! I couldn’t get the chocolate frosting to come out right, however — the butter oils separated and the cocoa powder stayed as chunky little powder pieces. I tried twice and couldn’t get it to melt together properly like yours in the video. Any ideas if I was over boiling or not boiling long enough?
Anyway, I just melted dark chocolate instead and poured that over top — it turned out great! Recommend!
Hi Rory,
Most likely the mixture was boiled to hot and too fast! Be sure to whisk it constantly and when it starts to boil and don’t boil it for more than the suggested 2 minutes. (You could even try removing it from the heat once it starts boiling)! Best of luck!