Peanut butter cookie bars are thick, buttery, and packed with melty chocolate chips. The edges turn lightly golden while the center stays soft and chewy, so they’re perfect for potlucks, lunchboxes, and freezing.
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Holly’s Recipe Highlights
- Flavor: Packed with classic peanut butter and chocolate chip goodness, plus deep caramel notes from the brown sugar.
- Why Make It: One-pan peanut butter cookie bars mean no chill time and no scooping required. Just bake, slice, and serve.
- Time-Saving Tip: Line the pan with parchment so you can lift, cool, and slice quickly.
- Serving Suggestions: Great straight from the pan, slightly warm, topped with ice cream, and a drizzle of hot fudge sauce or homemade caramel.
Key Ingredients and Easy Swaps
- Peanut Butter: Use creamy, shelf-stable peanut butter for consistent texture. Natural peanut butter can separate and make bars oily or crumbly.
- Brown Sugar: Adds moisture and a chewy texture. Dark brown sugar gives a deeper caramel flavor.
- Eggs & Butter: Classic cookie ingredients that work together to create the best flavor and texture. It’s okay to use margarine in place of butter, but don’t skip the eggs.
- Chocolate Chips: Semisweet balances the sweetness. Milk chocolate is sweeter, or mix chips and chunks for extra melty pockets. Mini chocolate chips work great for more chocolate in every bite.
Favorite Variations
- Peanut Butter Cup Bars: For more peanut flavor, stir in chopped peanuts for crunch, and replace the chocolate chips with chopped peanut butter cups.
- Salted Caramel Bars: Try adding a drizzle of easy caramel sauce after they cool and sprinkle with some flaky salt before slicing.
If you love these peanut butter desserts, try these peanut butter blossoms.
Mix, Spread, Bake, Slice
- Cream together the butter, peanut butter, and sugars. Mix in the remaining wet ingredients (full recipe below).
- In a medium mixing bowl, combine the dry ingredients.
- Gradually combine the two, mixing until just blended. Stir in the milk and fold in the chocolate chips.
- Spread into an even layer and bake until golden.
For perfect squares, let the bars cool completely before slicing.
How to Store Cookie Bars
- Room Temp: Store in an airtight container for up to 4 days. Tuck in a small piece of bread to keep the cookie bars soft.
- Fridge: Store in an airtight container for up to 7 days, and let them come to room temperature before serving.
- Freezer: Freeze sliced bars with parchment between the layers for up to 3 months. Thaw at room temperature.
- Reheat: Microwave a bar 8 to 12 seconds for melty chips, or warm briefly in a low 300°F oven.
Easy Bars and No Bake Treats
Did you make these Peanut Butter Cookie Bars? Leave a comment and a rating below.
Ingredients
- 1 cup unsalted butter softened to room temperature
- 1 cup creamy peanut butter
- 1½ cups light brown sugar tightly packed
- ½ cup granulated sugar
- 1 large egg + 1 large egg yolk
- 2 teaspoons vanilla extract
- 2¾ cups all-purpose flour
- 1 teaspoon cornstarch
- ½ teaspoon baking powder
- ¼ teaspoon salt
- 2 tablespoons milk
- 2 cups chocolate chips semisweet or milk chocolate
Instructions
- Preheat oven to 350°F and line a 9×13-inch pan with parchment paper (or lightly grease and flour the pan).
- In a large bowl, cream together butter, peanut butter, and sugars with a hand mixer until fluffy.
- Mix in the egg, yolk, and vanilla extract.
- In a medium bowl, whisk together flour, cornstarch, baking powder, and salt until well combined.
- Gradually add the dry mixture to the wet mixture until it is completely combined.
- Add milk and stir again until mixture is well incorporated.
- Fold in chocolate chips.
- Transfer batter to prepared pan and use a spatula to spread it evenly into pan.
- Bake for 35-40 minutes or until edges are just beginning to turn golden brown and a toothpick inserted in the center comes out clean or with a few moist crumbs.
- Allow to cool completely before cutting and serving.
Notes
- Use a parchment sling so the bars lift out easily and slice cleanly.
- Mix just until the flour is blended to keep the texture tender.
- Press dough firmly into the corners so the edges bake evenly.
- Remove when a toothpick shows a few moist crumbs and add some extra chips on top.
- Chill before slicing for neat, clean cuts.
Nutrition Information
Calories: 333 | Carbohydrates: 41g | Protein: 5g | Fat: 17g | Saturated Fat: 8g | Polyunsaturated Fat: 2g | Monounsaturated Fat: 5g | Trans Fat: 0.3g | Cholesterol: 30mg | Sodium: 89mg | Potassium: 110mg | Fiber: 1g | Sugar: 28g | Vitamin A: 284IU | Vitamin C: 0.1mg | Calcium: 45mg | Iron: 1mg
Nutrition information provided is an estimate and will vary based on cooking methods and brands of ingredients used.
Course Dessert, Party Food, Snack
Cuisine American© SpendWithPennies.com. Content and photographs are copyright protected. Sharing of this recipe is both encouraged and appreciated. Copying and/or pasting full recipes to any social media is strictly prohibited. Please view my photo use policy here.
Recipe updated 4/19/25
@spendwithpennies. i read tour comment about making these in a 13×9 pan. but they wouldn’t be as thick as made in a 9 inch square pan. so my question is. can this recipe be doubled for a 13×9 baking pan? a thicker bar?
That should be just fine LuAnn. If you try it I would love to hear how it turns out!
Excellent Food
Just made these in a 9×13 pan for 30 minutes. They are perfect cookie bars. They won’t seem done in the middle, but as they cool they will firm up. I love that the edges have a tender crunch and the inside is soft. Great with a glass of milk or cup of coffee.
That does sound perfect to me too Christine!
To make these bars in a 13×9 baking pan. Do you double the recipe? They look amazing
Hi LuAnn, I would double the recipe for that size of pan. If not, they will be much thinner.
These were awesome!!!!
I did increase the baking time , about 12 extra minutes and put the dough into a 9×13 glass baking dish. I stuck a knife in, they looked raw, but the knife came out clean.
I used chocolate chunks and chunky peanutbutter, 1
1/2 cups . They were very rich .
They reminded me of a friend’s peanut butter fudge, I had in my teens.
My family lives far away and are always asking for baked goods. Because these are so moist and tender, I know they will ship well, and not dry up. I made these over 2 weeks ago, and have a few left, that are still moist. I wish I could upload a picture to share.
Great recipe!!! Thanks for sharing it with everyone!!!
How lovely Kimberly! Thank you for sharing. How nice for you to send them to your family!
Made these today and they are perfection!
They were sooo delicious
Used 9×13 pan followed your recipe to the T had to bake way longer than you say. I have a chef oven so don’t tell me to check my temp. Just raw in the middle. Your recipe is terrible.
I’m sorry to hear that you didn’t enjoy it K. This recipe is usually a very popular reader recipe! Were your ingredients all at room temperature?
Delicious. I used 2/3 of the batter and put it in a 9×9 pan, baked at 350 degrees for 35 minutes. Worked perfectly. The other 1/3 I made into 16 round balls and cooked them on a cookie sheet, these baked for approximately 20 minutes at 350 degrees. Also worked perfectly. They are very sweet, so a little goes a long way. Thank you for the recipe.
This recipe did not work out for me. I bake nearly every day and I know that it isn’t my oven. I baked them in a 13×9 pan and after 45 minutes, the middle was still raw and the edges nearly burned. I’m not sure what went wrong, but I feel like a whole cup of butter and of peanut butter may just be too much moisture. I’d suggest one stick of butter.
I’m sorry this didn’t work out for you. Thank you for your suggetion.
Wonderful. I was a bit worried when I realized that the big bag of chocolate chips lurking in the back of the pantry was mini-morsels, but they worked fine.
Just what does the cornstarch add to the batter? I can’t recall seeing it in a cookie recipe before
Glad you enjoyed them Mary! The cornstarch mixed with the flour creates a tender and delicious cookie bar!
That was a waste of ingredients.
Oh no! Sorry to hear that Meghan. This recipe is usually a hit with readers. Is there anything specific that we can help with?
Made it vegan – split the recipe in half. Subbed the eggs out with Bob’s Red Mill egg replacer. Used Melt organic “butter” sticks. Only had “natural” peanut butter on hand thought it might be a little too oily but it isn’t. Bumped up the corn starch a bit and I’m heavy handed on the vanilla. All in all it came out great! Oh used a 11 3/4 by 7 1/2 glass baking dish @ 350 for 35 minutes in a convection oven.
I made this recipe in a 9×13” pan and it turned out fabulous! I’ve also used this recipe for chunky almond butter and milk chocolate chip bars. My oven tends to run a little cool, so I left them in for 37 minutes. This recipe also lends itself well to whole wheat pastry flour. Super versatile recipe!
Thank you for sharing Terri! Sounds like some great options!
I followed the recipe and at the 35 min mark I checked on it and the entire inside is still raw. I tried adding more time and decreased the temp. Didn’t turn out. Really sad
I am sorry the recipe didn’t work out for you Dena. Have you checked your oven temperature? I once had an oven that was baking nearly 60 degrees cooler than set.
My cookies came out soft in the middle I cooked them forever and didn’t come out like a cookie at all so sad what could have happened? I followed the recipe exact and even used a scale.
Hi Julia,
Have you ever checked your oven temperature? I hope this helps!
What should the bars look like on the inside? I am not positive they cooked all the way. I followed the exact directions and pan size. Still taste good and I love soft cookie types. Even added a few minutes cooking time didn’t want edges and top to get too dark. Any suggestions.
They’ll be very soft and chewy on the inside. You can see this in the photos in the post, that they’re very chewy, not cakey at all. Enjoy Theresa!
This is a great flavor combination but I agree with other commenters – they really need to be made in a bigger pan! And believe me I have nothing against a thick chewy cookie bar – it’s just crazy overkill for a 9×9. I dumped the unbaked dough out into a 9×13 and that’s better, but if I try it again, I’ll try to just halve the recipe or look for a less fussy alternative, sorry to say.
Wow why can’t people just make their own variations if they are not happy….It is her recipe not yours Monica. If you aren’t happy with it just make your own recipe. Sick of seeing people do this to others. Especially when they completely change someones recipe and rudely post it. People are just not very nice anymore. They get more pleasure out of insulting people. I can’t wait to try this with my granddaughter next weekend…looks great (especially the thickness) it’s a cookie bar like a brownie not a flat cookie….
Agree with you Tammy well said. I made them they turned out great.
Is it one 1/2 cup of brown sugar or is it 1 and 1/2 cup? You only wrote 1/2 cup (regular) sugar so I’m thinking it’s 1 and 1/2 cups but since you didn’t pluralize the cup like you did for the 2 3/4 cups of flour I’m confused. I may be way over thinking this as well. Thanks for clarification.
It’s 1 and ½ cups. I’ve updated the cups to make it more clear! Thank you for asking Peg. Enjoy the bars!
I made mine in a 13 X 9 metal pan because I wanted to have more pieces. They still came out nice and thick and are delicious!! This is such an easy recipe…used part light and dark brown sugar only because I had to without running to the store for more light brown. They were perfect. This is an excellent recipe Holly!! With my homemade peach pie and these for dessert, we’re going to have an awesome Fathers Day dinner!! Many thanks!
That’s great Julie!
Can I use dark brown sugar – how will they be different?
I have only made the recipe as written, so can’t say for sure, but it may make them slightly chewier. Let us know if you try it Ruth!
you definitely need a bigger pan, i did mine in a jelly roll pan!