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
The bars were wonderful. Thank you. Can they be frozen?
Yes, these cookie bars freeze well.
I really liked the Peanut Butter Chocolate Chip Cookie Bars. They turned out perfectly; however, I felt like that taste was lacking when it came to the peanut butter.
For extra peanut butter flavor you could try replacing the chocolate chips with peanut butter chips. I would love to hear how that turns out for you!
I am a big fan of your recipes and many from Sugar Spun Run, as well. Unfortunately, these came out terrible. I agree with many of the other comments, that a 9×13 would have been ideal. I’m so disappointed. After leaving them in the oven for 70 minutes, DOUBLE the suggested baking time, I gave up and took them out. They were still completely raw in the middle. What a disappointment and waste of my time and money. Sorry.
Thank you for sharing your experience Ali. I’m sorry that these bars didn’t work out for you, I can understand how disappointing that is. We retested and updated the recipe, adjusting both the pan size and baking instructions. Thanks so much for your honest feedback; it truly helps us improve!
I am currently making them. I would agree a 9×13 pan would definitely be better. Not sure why a 9×9 pan was used? Mine is currently in a 9×9 pan and concerned they will not cook. Will end up covering them with foil so they don’t burn.
I just made these and they turned out fantastic! I forgot to put the milk in but didn’t seem to hurt it at all. I did use peanut butter powder (hydrated) and they were a big hit!
Love the recipes
Holly, I really love your recipes! I’ve been cooking and baking 40+ years. I lost most of my cookbooks due to a flood so resort to your site often.
This chocolate chip peanut butter bars recipe came out AWFUL! Never have I used/seen cornstarch in a cookie or bar recipe… sign #1, sign #2 I asked, who’s Samantha?
I was utterly embarrassed when I brought these bars to a family dinner, they were very dry!
Thank you so much for your kind words and for loving my recipes—I’m really sorry these bars didn’t turn out how you expected, especially for a family dinner. I know how frustrating that can be!
To clarify, cornstarch is often used in cookies and bars to create a softer texture, helping to keep baked goods tender. It’s similar to how pudding mix works in some cookie recipes.
As for Samantha, she was a contributor I know and trust. She has a lot of baking expertise and has created many well loved dessert recipes.
BEST PB cookie bar recipe I have found so far and I’ve tried a ton of them looking for the best recipe! The key to getting a perfect bake on bars or brownies is to learn to use a digital thermometer and check the center of the bars when the temp is between 170 – 200 F they are done. It is your personal preference when you pull them out of the oven but it needs to be between these temps. You will never over or under bake them this way.
Great tasting but I used a 9×13 pan as there was too much dough for a 9×9 pan. As a long time baker I could tell trying to use a smaller pan would never bake through.
Thank you for trying our recipe! I am glad you enjoyed it.
This is one of the WORST cookie bar recipes I have ever made. I left it in for at least 15 extra minutes and finally had to take it out as it looked like it was getting too dark. After letting cool, it was basically RAW cookie dough in the middle. What a waste of my time and ingredients. Definitely do NOT recommend.
Sorry this recipe didn’t work out for you, Denise!
Hi.
Would this recipe still be good if frozen after its baked?
Thank you!
Patty
Hi Patricia, I think it should taste fine after being frozen. I would love to hear how it turns out for you!
OMG! Delicious! I only had chunky peanut butter but these bars are AMAZING!
Made these today for a church function. Subbed 1/2 butterscotch chips for some of the chocolate chips. Baked it in a9x13 pan and they were perfect! So good!
Made these but I’m not sure they’re safe to eat – dough is basically raw in the middle. Edges nice and brown, though. Recommend larger baking dish as 9×9 does make thick bars but they just don’t cook! Frustrating to spend money and time on recipes that fail…
Sorry to hear this recipe didn’t work out as expected, Kathy. If you do try it again in a larger pan we would love to hear how it turns out for you!
Really good! I did use Jif Natural and seemed fine, but that is not an oily PB. I also threw in some peanut butter chips I had. About 2/3 cup and I did 1 1/2 chocolate. Used 9 x 13 pan and took about 30 min. I was looking for a peanut butter chocolate chip bar recipe, and this was a home run! I have made a lot of Spend with Pennies recipes and knew because it was theirs, it would be good!