Peanut Butter Cookie Bars
Easy Peanut Butter Cookie Bars with peanut butter cups are soft and chewy bar cookies baked in an 8×8 square pan. They’re sweet, salty, and delicious!

Why does life have to be so complicated?
Every thought we think, every decision we make, there is always a long list of what ifs and why nots, of benefits and consequences.
When do we think smart and when do we trust our heart? When do we hold back and when do we jump? When is it ok to keep going and when have we had enough?
I can’t make these complicated decisions go away, but I can bring you one of the easiest bar cookies to make: Peanut Butter Cookie Bars!
They’re soft and chewy peanut butter bars that are nutty, sweet, and salty. Ideally they’re peanut butter chocolate chip cookie bars but instead of chocolate chips, I used chopped up peanut butter cups.
Not to be confused with my peanut butter blondies because you cream the butter together with the sugar instead of melting it, creating a more tender cookie texture.
These peanut butter bar cookies are super easy to bake from scratch when you don’t want to do any rolling, chilling, cutting, or decorating.
Just make your cookie dough like with my small batch peanut butter cookies but instead of rolling, just pat into the bottom of your 8×8 pan.

Ingredients For Peanut Butter Cookie Bars
Here’s what you need to make your peanut butter bar cookies:
- All-purpose flour: Standard baking flour to balance the liquid ingredients
- Baking soda: Leavening agent so your bars rise and have that soft cookie texture
- Salt: Brings out the flavor of the cookie
- Peanut butter: These peanut butter bars have been tested with your typical processed peanut butter because it has the most consistent result. Natural peanut butter can vary in results.
- Butter: Helps the dough spread and rise while baking.
- Brown sugar: Use fresh, soft brown sugar as dry brown sugar will result in a crumbly dough. It also reacts with the baking soda due to its acidity from the molasses.
- Granulated Sugar: Adding white sugar with brown sugar contributes to the cookie’s chewy texture.
- Egg: Helps bind the dough together
- Vanilla: Really brings out the peanut butter flavor
- Peanut butter cups: Adds extra peanut butter flavor, but you can easily substitute chocolate chips

How To Make Peanut Butter Cookie Bars
Here’s how to make your peanut butter chocolate chip cookie bars:
- Cream together your peanut butter, butter, granulated sugar, and brown sugar.
- Beat in egg and vanilla.
- Add flour, baking soda, and salt until a dough forms then add peanut butter cups.
- Bake at 350F for 20 minutes or until golden brown and toothpick comes out clean.
Store leftovers in an airtight container for up 1 week.

Do peanut butter bars need frosting?
Your cookie bars will be absolutely delicious as is but if you really want to take them one step further, add frosting on top!
Chocolate frosting would be the ultimate pairing, but you can also double the nuttiness with peanut butter frosting.

Why are my peanut butter cookie bars crumbly?
Nothing is as sad as a crumbly cookie! Here’s what may have gone wrong:
- Too much flour: It’s important to measure your flour using the spoon and level method rather than the scoop and pack method. Learn more about how to measure flour.
- Dry brown sugar: Sometimes brown sugar dries out and becomes really crumbly. Rehydrate it using a brown sugar softener or adding a slice of bread to your container.
- Overbaked: Keep an eye on your baking time and ensure your oven temperature is accurate using an oven thermometer.
- Wrong peanut butter: Using natural peanut butter is oiler and less sweet, which will make your cookie bars a bit crumblier.
More Peanut Butter Dessert Recipes
If you enjoyed making your peanut butter cookie bars, check out my other peanut butter desserts:
- No Bake Peanut Butter Bars
- Peanut Butter Brownies
- Peanut Butter Sandwich Cookies
- Peanut Butter Stuffed Cookies
- Microwave Peanut Butter Cookie

Peanut Butter Cookie Bars
Easy Peanut Butter Cookie Bars with peanut butter cups are soft and chewy bar cookies baked in an 8×8 square pan. They’re sweet, salty, and delicious!
Ingredients
- 1 cup all-purpose flour
- 1/2 teaspoon baking soda
- 1/4 teaspoon table salt
- 1/2 cup creamy processed peanut butter (not natural)
- 1/4 cup (2 ounces or 4 tablespoons) unsalted butter, softened
- 1/4 cup packed brown sugar (soft and moist, not dry and crumbly)
- 1/4 cup granulated sugar
- 1 large egg, room temperature
- 1 teaspoon vanilla extract
- 1/2 cup chopped peanut butter cups, peanut butter chips, or semisweet chocolate chips
Instructions
- Preheat oven to 350F. Line an 8x8 pan with parchment paper.
- In a medium bowl, stir together the flour, baking soda, and salt.
- In a large mixing bowl on medium-high speed (with paddle attachment if using a stand mixer), beat together the peanut butter, butter, granulated sugar, and brown sugar until creamy, 1 minute.
- Scrape down the bowl then beat in egg and vanilla.
- Turn the speed down to low then gradually beat in the flour mixture. Stir in peanut butter cups.
- Transfer dough to the pan then bake 18-20 minutes or until golden brown, edges pull away, and a toothpick comes out clean (may get some chocolate). Cool completely before cutting.
Store in airtight container for up to 5 days.
Notes
- If you enjoyed this recipe, check out Small Batch Peanut Butter Cookies and Peanut Butter Blondies.
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Peanut butter cups always answer all my life questions :-) I love all the pb cups peeking out of these yummy bars!!!
It doesn’t matter what the question is right? Seems like chocolate and peanut butter is the perfect solution ;) Thanks Jocelyn!
ooo yum! I love Peanut Butter Cups! I’d love a bar!
Thanks Nicole!
Those peanut butter cup bars would brighten any day of mine. I seriously love peanut butter and chocolate. And I’m with you on the baking to help calm a stressed day. I don’t know which part I like the most, the mixing or the aroma of it baking or perhaps the enjoyment of it when it’s all done.
Let’s go with all of the above! Thanks Renee.
I want these. Now. Oh my. You’re definitely a gal after my heart with these!
Well come visit and you can have some ;)
Mmmm love pb cups and love how simple and easy and peerfectly delicious these look
Thanks Kayle!
I love simple recipes like this. Sometimes, easier is better! These look so darn good. I’d eat them for breakfast, lunch, and dinner.
Don’t forget midnight snack ;) Thanks Colleen!
Carla, we both had the same idea on Friday night – baking our woes away! These bars look phenomenal – peanut butter and chocolate cures everything, in my opinion. Love the styling here.
Yes, baking, chocolate, and peanut butter can bring world peace haha thanks Nancy!
These would soothe my soul. It is always nice to do something for yourself on a Friday night.
Thanks Emily!
Carla,
Really, the take home message for me was that your photos of Friday night baking turn out so much better than mine!
I know I was baking pizzas, not yummy-looking bars, and perhaps a chicken cranberry pizza with fresh mozzarella on a blueberry crust is not as photogenic as a PB cup, but still.
I love your photos!
If you bake the pizzas, I will bake more of these bars! Thanks Kirsten!
I love this, I did something similar in cookies and banana bars a while back. SOOOO good
Mmm bananas would make a great addition!
Chocolate and peanut butter is my favorite flavor combo, and these bars look so so good. I need to try these!
Thanks Rachel!
The peanut butter bars sound wonderful however you forgot to mention “when” to add the flour mixture in the recipe.
Fixed! Thanks for letting me know.
Your bars look so delicious :) Life is ridiculously complicated and full of big decisions, but I know baking definitely helps to calm me down when I’m feeling really stressed about it!
Baking solves everything it seems :) Thanks Rosie!
” I just wanted to do some mindless baking to soothe my soul as work beats me hard during the week.” This is exactly how I felt when I saw your recipe. Thanks for sharing!
Made these. They are very easy, with few ingredients. Took only 20-30 total. Thanks for the “go to” snack for school!
Awe…I’ll hold your hand and guide you. You bake these bars. ;)