Name: Peanut Butter Cookie Bars
Prep time: 10 min
Cook time: 25 min
Total time: 35 min
Cuisine: American
Ingredients: 1/2 cup (1 stick) unsalted butter, melted; 1 cup packed light brown sugar; 1/2 cup creamy peanut butter (not natural style); 1 large egg; 1 large egg yolk; 2 teaspoons vanilla extract; 1 1/4 cups all-purpose flour; 1/2 teaspoon baking powder; 1/4 teaspoon baking soda; 1/2 teaspoon salt; 1/2 cup peanut butter chips (optional); 1/2 cup chocolate chips (optional)

The aroma of Peanut Butter Cookie Bars baking in the oven instantly transports me back to my grandmother’s kitchen—that distinctly nutty, sweet scent wafting through the house, promising something wonderful was about to emerge from the oven. These Peanut Butter Cookie Bars combine everything I love about a classic peanut butter cookie but in a gloriously chewy, time-saving bar form that will make you wonder why you ever bothered with individual cookies in the first place.

I stumbled upon this Peanut Butter Cookie Bars recipe during a particularly chaotic holiday season three years ago. With a house full of guests and a to-do list a mile long, I needed a crowd-pleasing dessert that wouldn’t keep me tied to the kitchen. These bars were my salvation! I mixed the dough in one bowl, spread it in a pan, and 25 minutes later had enough delicious Peanut Butter Cookie Bars to feed everyone without having to roll and flatten dozens of individual cookies.

My sister-in-law, who claims to be “just not a dessert person” (a concept I still struggle to understand), ate three of these Peanut Butter Cookie Bars in one sitting and immediately requested the recipe. That’s when I knew I had a winner on my hands. The beauty of these bars lies in their perfect texture—crisp around the edges but gloriously soft and chewy in the center, with that rich peanut butter flavor in every bite.

Let me show you how easily these Peanut Butter Cookie Bars come together and why they deserve a permanent spot in your baking rotation.

These Peanut Butter Cookie Bars are ready in 30 minutes from start to finish—perfect for last-minute entertaining or satisfying urgent sweet cravings
The Peanut Butter Cookie Bars recipe uses simple pantry staples you likely already have on hand
No scooping, rolling, or flattening individual cookies—just spread the dough in a pan and bake
These Peanut Butter Cookie Bars stay fresh and chewy for days, making them perfect for make-ahead treats
The recipe is easily customizable with mix-ins like chocolate chips, candy pieces, or different nut butters
Peanut Butter Cookie Bars freeze beautifully for up to 3 months—perfect for emergency dessert stashes

1/2 cup (1 stick) unsalted butter, melted
1 cup packed light brown sugar
1/2 cup creamy peanut butter (not natural style)
1 large egg
1 large egg yolk
2 teaspoons vanilla extract
1 1/4 cups all-purpose flour
1/2 teaspoon baking powder
1/4 teaspoon baking soda
1/2 teaspoon salt
1/2 cup peanut butter chips (optional)
1/2 cup chocolate chips (optional)

Ingredient Tips:

For the peanut butter, conventional creamy brands like Jif or Skippy work best in these Peanut Butter Cookie Bars. Natural peanut butter that separates can make the bars too oily or dry.
The extra egg yolk is my secret for ultra-chewy bars—don’t skip it!
Brown sugar provides moisture and a deeper flavor than white sugar. Dark brown sugar works too for an even more caramel-like flavor.

Prepare the Batter

Preheat your oven to 350°F (175°C). Line an 8×8-inch or 9×9-inch square baking pan with parchment paper, leaving some overhang on the sides for easy removal.
In a large bowl, whisk together the melted butter and brown sugar until well combined and smooth.
Add the peanut butter and whisk until fully incorporated and the mixture is smooth and uniform.
Add the egg, egg yolk, and vanilla to the peanut butter mixture. Whisk until smooth and well-blended.
In a separate bowl, whisk together the flour, baking powder, baking soda, and salt.
Add the dry ingredients to the wet ingredients and stir just until combined. Don’t overmix—this helps keep your Peanut Butter Cookie Bars tender.
Fold in the peanut butter chips and chocolate chips if using. The dough will be thick and somewhat sticky.

Bake the Bars

Transfer the dough to your prepared baking pan and spread it evenly using a spatula or slightly dampened hands.
For a traditional touch, use a fork to make crosshatch marks on top of the dough, just like classic peanut butter cookies.
Bake for 22-25 minutes until the edges are lightly golden and the center appears set but still soft. For chewy Peanut Butter Cookie Bars, slightly underbaking is better than overbaking.
Allow the bars to cool completely in the pan on a wire rack before removing and cutting into squares. This cooling period is crucial for the perfect chewy texture of your Peanut Butter Cookie Bars.

Serve and Store

Cut into 16 squares (or 9 larger bars if you’re feeling generous) once completely cooled.
Store in an airtight container at room temperature for up to 5 days, though I doubt they’ll last that long!

The key to chewy bars is not overbaking them. They might look slightly underdone in the center when you take them out, but they’ll continue to set as they cool.
For extra peanut butter flavor, try drizzling melted peanut butter chips over the top after baking, or swirl in some jam before baking for a PB&J-inspired treat.
Make-ahead option: You can prepare the dough up to 24 hours in advance and refrigerate it. Let it come to room temperature for about 20 minutes before spreading in the pan and baking.
Storage instructions: These Peanut Butter Cookie Bars freeze beautifully! Wrap individual bars in plastic wrap, then store in a freezer bag for up to 3 months. Thaw at room temperature for about an hour before enjoying.

Can I use crunchy peanut butter instead of creamy?

Yes! Crunchy peanut butter works perfectly in these Peanut Butter Cookie Bars and adds a nice textural contrast. Just be aware that the bars will have a slightly different texture with visible peanut pieces throughout.

Why did my bars turn out dry?

The most common reason for dry Peanut Butter Cookie Bars is overbaking. Remember that they continue to set as they cool, so it’s better to pull them from the oven when they still look slightly underdone in the center. Also, make sure you’re measuring your flour correctly—too much flour can result in dry bars.

Can I double this recipe for a larger batch?

Absolutely! Double all ingredients and bake in a 9×13-inch pan. You’ll need to increase the baking time by about 5-7 minutes, but still watch carefully to avoid overbaking your Peanut Butter Cookie Bars.

What mix-ins work well with these bars?

These Peanut Butter Cookie Bars are incredibly versatile. Try adding chopped peanut butter cups, white chocolate chips, butterscotch chips, pretzel pieces for a sweet-salty combo, or even a layer of jam in the middle for a PB&J version.

Can I make these with almond or other nut butters?

Yes, though the flavor and texture will change slightly. Almond butter usually creates a slightly drier bar, so you might want to add an extra tablespoon of melted butter to the batter.

These Peanut Butter Cookie Bars have become my go-to dessert whenever I need something foolproof and crowd-pleasing. They blend the nostalgic flavor of a classic peanut butter cookie with the ease and simplicity of a bar—creating a treat that feels both comforting and just a little special. If you’re a fan of chewy, buttery desserts like the irresistible peanut butter cookies, you’re going to fall in love with this recipe.

The real beauty of these Peanut Butter Cookie Bars is their versatility. Dress them up with a scoop of vanilla ice cream for an easy dessert, pack them into lunchboxes for a fun surprise, or enjoy them with your afternoon coffee—much like you would a soft, chewy brookie bar. Their chewy texture and deep peanut butter flavor make them irresistible in any setting.

If you enjoyed this recipe, you might also love:

Sweet Potato Brownies – moist, chocolatey, and nutrient-packed
Easy Churro Cheesecake – a layered dessert that’s as fun as it is delicious
Banana Bread Cookies – a hybrid treat perfect for cookie and quick bread lovers

Have you tried making Peanut Butter Cookie Bars before? What’s your favorite way to enjoy them—warm with a scoop of ice cream, or chilled straight from the fridge? Share your baking adventures in the comments below—I’d love to hear from you!

Peanut Butter Cookie Bars