Name: Peanut Butter Chocolate Chip Cookie Bars
Prep time: 15 min
Cook time: 35 min
Total time: 50 min
Cuisine: American
Ingredients: 1 cup unsalted butter, softened; 1 cup creamy peanut butter; 1½ cups light brown sugar, packed; ½ cup granulated sugar; 1 large egg + 1 egg yolk; 2 tsp vanilla extract; 2¾ cups all-purpose flour; 1 tsp cornstarch; ½ tsp baking powder; ¼ tsp salt; 2 tbsp milk; 2 cups semi-sweet chocolate chips

Why You’ll Love This Recipe

I love how easy and reliable this recipe is. The texture is everything I want in a cookie bar—soft, dense, and full of melty chocolate chips. The peanut butter adds that rich, nutty flavor that pairs perfectly with the sweetness of brown sugar and chocolate. These bars are a guaranteed crowd-pleaser.

ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

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 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 semi-sweet chocolate chips

directions

I start by preheating the oven to 350°F and lining a 9×13-inch baking pan with parchment paper or lightly greasing it.

In a large bowl, I use an electric mixer to cream together the butter, peanut butter, brown sugar, and granulated sugar until everything is smooth and well combined.

Next, I add the egg, egg yolk, and vanilla extract, mixing until fully incorporated.

In a separate bowl, I whisk together the flour, cornstarch, baking powder, and salt. I gradually mix the dry ingredients into the wet until just combined.

Then I stir in the milk and fold in the chocolate chips.

I spread the thick batter evenly into the prepared baking pan.

These bake for 35 minutes, or until the edges turn golden and a toothpick inserted into the center comes out with just a few moist crumbs.

Once done, I let them cool completely in the pan before cutting into 24 bars.

Servings and timing

This recipe yields 24 cookie bars.
Prep Time: 15 minutes
Cooking Time: 35 minutes
Total Time: 50 minutes
Calories: 333 kcal per bar

Variations

I sometimes mix in chopped nuts like walnuts or pecans for added crunch. Swapping out the semi-sweet chips for white chocolate or peanut butter chips also gives a fun twist. For a saltier contrast, I sprinkle a bit of flaky sea salt on top before baking.

storage/reheating

I keep these bars in an airtight container at room temperature for up to 4 days. They can also be refrigerated to stay fresh longer, or frozen for up to 2 months. When reheating, a quick 10-second zap in the microwave brings back that fresh-from-the-oven texture.

FAQs

Can I use natural peanut butter in this recipe?

I prefer using regular creamy peanut butter, as natural versions can separate and affect the texture.

Why do I need an extra egg yolk?

That extra yolk adds richness and helps create a chewier texture.

Can I use a different size pan?

Yes, but I adjust the baking time accordingly. A smaller pan makes thicker bars and takes longer to bake.

How do I know when they’re done baking?

The edges should be golden, and a toothpick in the center should come out with a few moist crumbs, not wet batter.

Can I make these gluten-free?

Yes, I’ve used a 1:1 gluten-free flour blend with good results, though the texture might vary slightly.

Conclusion

These peanut butter chocolate chip cookie bars are everything I want in a dessert—easy, delicious, and loaded with flavor. They’re perfect for bake sales, potlucks, or just a quiet treat at home. One batch, and I’m already planning the next.