Peanut Butter Cookie Bars

These peanut butter cookie bars are the ultimate decadent treat. They’re made with simple ingredients and come together in less than 30 minutes. No one will be able to resist!

I love coming up with new ways to reimagine peanut butter desserts. 

Seriously, it’s guaranteed that anything with peanut butter will be an instant hit in my house. We’ve added it to peanut butter brownies and made peanut butter granola, and now we’ve made the perfect chewy peanut butter cookie bars.

Thick and chewy cookie bars with creamy peanut butter and chocolate chunks, every bite explodes with flavor. If you bring these to a party, I promise they’ll be gone before you know it!

Table of Contents

1. Recipe highlights
2. Ingredients needed
3. How to make peanut butter chocolate chip cookie bars
4. Recipe tips and variations
5. How to store leftovers
6. More dessert bar recipes to try
7. Peanut Butter Cookie Bars (Recipe Card)

Recipe highlights

• Simple ingredients. Nothing complicated here, just basic, easy-to-find ingredients, most of which you probably have on hand. 
• Peanut butter chocolate flavor in each bite. If you love the peanut butter chocolate combo as much as I do, then you’ll love these cookie bars. 
• A make-ahead treat. These bars taste just as good fresh as they do on day one or two, so feel free to make them in advance and store them in the fridge until you’re ready to serve. 

I keep this recipe simple so the peanut butter is what stands out, but there’s plenty of room to switch up the ingredients, whether they need to be vegan or gluten-free. 

Ingredients needed

As mentioned earlier, this recipe calls for pretty simple baking staples. Here’s exactly what you’ll need to make the cookie bars:

• Butter. I used unsalted butter so I have complete control over how much salt gets added to the bars.
• Coconut sugar. I enjoy coconut sugar for its subtle caramelized notes, but you could use light brown sugar. 
• Maple syrup. For extra sweetness and to bind the ingredients together. 
• Peanut butter. Smooth, drippy peanut butter with no sugar added. If you want to make my homemade honey roasted peanut butter recipe, reduce the maple syrup by half. 
• Vanilla extract. A key ingredient to any good baking recipe!
• Egg. Room-temperature eggs are best. 
• Self-rising flour. I used self-rising flour specifically because it already has baking powder and salt added to it. If you’re using all-purpose flour, add 2 teaspoons of baking powder and ¼ teaspoon salt. 
• Chocolate chips. I used semi-sweet chocolate chips, but you can use whatever chocolate chips you have on hand. 

How to make peanut butter chocolate chip cookie bars

I’ve included step-by-step photos below to make this recipe easy to follow at home. For the full printable recipe instructions and ingredient quantities, scroll to the recipe card at the bottom of this post.

Step 1- Prep work. Preheat the oven to 350F/180C and line a square baking pan with parchment paper. 

Step 2- Cream butter and sugar. In a large mixing bowl or the bowl of a stand mixer, add the butter, coconut sugar, and maple syrup. Beat until creamy and fluffy.

Step 3- Add the rest of the ingredients. To the bowl, add the peanut butter, vanilla, and egg. Mix until combined. Add the flour until combined, then stir the chocolate chips into the flour mixture.

Step 4- Transfer, bake, cool. Transfer the batter to the lined baking dish and bake in a preheated oven for 25 minutes or until a toothpick inserted in the center comes out clean. Let the cookie bars cool completely before slicing. 

Recipe tips and variations

• Use good-quality peanut butter. Trust me, now is not the time for Skippy or Jif. You’ll want to use your best peanut butter since it’s the bulk of these cookie bars. 
• Swap the peanut butter. If you’re not a peanut butter fan or you have an allergy, use other nut butters like almond butter or cashew butter. For a nut-free recipe, use sunflower seed butter or tahini.
• You’ll know the bars are done when they’re golden brown on top, slightly crisp on the edges, and a toothpick inserted in the center comes out clean.
• Avoid overbaking. The bars will continue to cook after they’ve been removed from the heat, so if you wait until they’re firm in the middle, they can become overcooked. 
• Cover in foil. If the tops of the cookie bars brown too quickly, you can cover them in foil to prevent burning. 
• Make them vegan. Use plant-based butter and vegan chocolate chips, and swap the egg for 1 flax egg made with 3 tablespoons of flaxseed and 1 tablespoon of water. 
• Make them gluten-free. Use gluten-free self-rising flour. 
• Experiment with mix-ins. Fold in some Reese’s pieces, M&Ms, chopped nuts, peanut butter chips, or top them with chocolate frosting. 

How to store leftovers

To store: Store the leftover peanut butter bars in an airtight container at room temperature for up to 1 week or in the fridge for 2 weeks. 

To freeze: Let the bars cool completely, then wrap them in foil or plastic wrap and freeze them in a freezer bag for up to 6 months. Thaw the bars overnight before enjoying them, or pop them in the microwave and heat them in 15-second intervals. 

More dessert bar recipes to try

• Caramel slice– Layers of buttery shortbread, gooey caramel, and delicate milk chocolate topping. 
• Zucchini bars– The perfect way to sneak in those extra veggies!
• Blueberry bars– Soft, chewy, and topped with a gorgeous crumb topping.
• Banana blondies– Full of banana and chocolate flavor, with zero baking required. 
• No-bake cookie dough bars– My family’s current obsession!