Click Here to Pin this Recipe for Later!

Why You’ll Love These Easy Double Chocolate Cookie Bars

These double chocolate chip cookie bars aren’t just a dessert; they’re a chocolate experience. From their incredibly straightforward preparation to their decadent flavor, here’s why they’ll quickly become a staple in your baking repertoire:

1. Rich Brownie Flavor & Fudgy Cookie Texture: Imagine the deep, intense chocolate flavor of your favorite fudgy brownie perfectly combined with the chewy, soft texture of a classic cookie. That’s exactly what you get with these bars. They’re so incredibly rich and satisfying, they could easily be called “brownie cookie bars.” This unique combination makes them an absolute dream for any true chocolate lover looking for the best of both worlds in a single bite.
2. One Bowl, No Mixer Required: Say goodbye to stacks of dirty dishes and the hassle of pulling out your heavy stand mixer! This recipe utilizes melted butter, which means you can ditch the electric mixer and simply use a spatula or whisk to combine all your ingredients. It’s perfect for busy weeknights, impromptu baking sessions, or when you just want a delicious treat without all the fuss. Less cleanup, more enjoyment!
3. Ready in Under 30 Minutes: When a serious chocolate craving strikes, waiting around for a complicated recipe is simply not an option. These quick double chocolate chip cookie bars are designed for speed and convenience, allowing you to whip up a batch from start to finish in less than half an hour. They’re an ideal last-minute dessert or a speedy way to treat yourself and your loved ones.
4. Perfect for Sharing (or Not!): Cookie bars are inherently easier to transport and share than individual cookies. Simply slice them into squares, and you have a perfect treat for potlucks, parties, lunchboxes, or a casual gathering. Of course, they’re also perfect for keeping all to yourself – we won’t tell!

Bake for a special occasion! If you adore these easy chocolate cookie bars, you must try my Triple Chocolate Cookie Cake next! It uses the same delicious base dough but is adorned with a fun, festive chocolate frosting border, making it ideal for birthdays and celebrations.

Essential Ingredient Notes for Perfect Double Chocolate Cookie Bars

This section provides helpful insights into the ingredients. For precise measurements and condensed instructions, please jump down to the full recipe card at the bottom of the page.

• Unsalted Butter: I strongly recommend using unsalted butter for this recipe. This allows you complete control over the salt content, ensuring your chocolate cookie bars have the perfect balance of sweetness and a hint of savory. Since we’re using melted butter, there’s no need to soften it beforehand, adding to the ease of this one-bowl recipe!
• Unsweetened Cocoa Powder: The type of cocoa powder you use significantly impacts the final flavor. I specifically tested this recipe with Hershey’s unsweetened cocoa powder, as it’s a widely available and affordable grocery-store brand that delivers a consistent, rich chocolate flavor. It’s crucial to use baking cocoa, not the sweetened cocoa mix used for hot chocolate, as these are entirely different products and will yield very different results. Natural unsweetened cocoa powder (like Hershey’s) tends to be more acidic and reacts with baking soda to create lift, contributing to the fudgy yet soft texture.
• Chocolate Chips: While semi-sweet chocolate chips are my go-to for these bars, feel free to get creative with your chocolate choices!
  • White chocolate chips: Add a lovely creamy contrast.
  • Milk chocolate chips: For an even sweeter, milder chocolate experience.
  • Dark chocolate chips: If you’re a fan of deep, intense chocolate, dark chocolate chips are fantastic. However, since the base itself is already very rich, I recommend reducing the amount to about 1 cup total to prevent the bars from becoming overly bitter or intensely rich for some palates.
  • Other Mix-ins: Don’t stop at just chocolate! Peanut butter chips, mini M&M’s, chopped nuts, or even toffee bits would be delicious additions.
• Eggs: The recipe calls for 1 whole large egg plus 1 extra egg yolk. The additional egg yolk adds richness and helps create that signature fudgy, chewy texture that we all love in a good cookie bar. Using room temperature eggs can also help them incorporate more smoothly into the batter.
• Sugars (Brown & Granulated): The combination of light brown sugar and granulated sugar is key. Brown sugar adds moisture and chewiness, contributing to the fudgy texture, while granulated sugar ensures a crisp edge and overall sweetness.
• All-Purpose Flour: Make sure to measure your flour correctly. Spoon the flour into your measuring cup and then level it off with a straight edge (like the back of a knife) to avoid adding too much, which can lead to dry bars.

Step 1: Prepare the Decadent Dough

This is where the magic begins, all in one bowl!

1. First, preheat your oven to 350°F (175°C). Then, in a medium-sized microwave-safe bowl, melt the unsalted butter (¾ cup, or 1 ½ sticks). This should take about 30-60 seconds, depending on your microwave. It’s crucial that the butter is fully melted but not steaming hot. If it’s steaming, allow it to cool for a few minutes. Using butter that’s too hot can lead to greasy cookie bars and might even partially cook your eggs when added, so patience here is key.
2. Next, add the light brown sugar (¾ cup) and granulated sugar (½ cup) directly into the melted butter. Use a sturdy spatula to stir vigorously until the sugars are completely incorporated and the mixture is smooth. Stir in the 1 whole egg, 1 extra egg yolk, and vanilla extract (2 teaspoons). Mix until just combined, ensuring everything is well integrated without overmixing.
3. Once your wet ingredients are beautifully blended, stir in the baking soda (¾ teaspoon) and salt (¾ teaspoon). These leavening agents and flavor enhancers will work their magic to create the perfect texture and balance the sweetness.
4. Finally, add the unsweetened cocoa powder (¾ cup) and all-purpose flour (1 ½ cups). Begin to mix these dry ingredients into the wet. Before all the flour has completely disappeared into the dough (you should still see a few streaks of flour), fold in 1 ¼ cups of chocolate chips. Continue mixing just until all the flour streaks are gone and the chocolate chips are evenly distributed. Be careful not to overmix the dough, as this can lead to a tougher, cake-like texture rather than the desired fudgy one. Immediately proceed to the next step to prevent overworking the dough.

Step 2: Press into Pan & Bake to Perfection

Getting your bars ready for the oven is simple, and just a few extra touches can make all the difference!

Lightly grease a metal 9×13″ pan, or for easiest removal and cleanup, line it with parchment paper, leaving an overhang on the sides to create “handles.” Press the prepared cookie dough evenly into the bottom of the pan until it’s smooth and flat. I find it helpful to place another piece of parchment paper on top of the dough and use my hands or the bottom of a measuring cup to achieve a perfectly smooth and even surface. This ensures uniform thickness for even baking. Sprinkle the remaining ¼ cup of chocolate chips generously over the top of the dough and gently press each one into the surface. This creates those beautiful melty pools of chocolate on top when baked.

Bake in your preheated oven at 350°F (175°C) for 14-16 minutes. Keep a close eye on them; you want the center to no longer look wet, but still appear slightly underbaked, as they will continue to set as they cool. Do not overbake! Overbaking is the biggest culprit for dry, crumbly, or even bitter-tasting chocolate bars. Remove the entire pan from the oven and immediately place it on a wire cooling rack. If desired, a sprinkle of flaky sea salt right after baking adds a wonderful textural and flavor contrast.

Step 3: Cool & Cut into Perfect Squares

Patience is a virtue, especially when it comes to cutting perfect cookie bars!

It’s crucial to allow the cookie bars to cool completely in the pan before attempting to remove and slice them. This can take a couple of hours. Cooling allows the bars to set properly, ensuring they are firm enough to cut cleanly without crumbling or smearing the melted chocolate. Once fully cooled, use the parchment paper overhang to lift the entire slab of cookie bars out of the pan. Slice them into 12-24 squares, depending on your desired portion size, then enjoy your homemade treats!

To keep your delicious double chocolate cookie bars fresh, cover the pan tightly with plastic wrap or transfer the cut squares to an airtight container. They are best enjoyed within 2-3 days, as they tend to start drying out after the second day. See the notes below for valuable freezing tips to extend their life.

Expert Tips & Delicious Variations for Your Double Chocolate Cookie Bars

Elevate your cookie bar experience with these helpful hints and creative ideas:

• Don’t Overmix the Dough: This is a critical tip for achieving that perfect dense, fudgy texture. I highly recommend mixing the dough by hand with a spatula rather than an electric mixer. Overmixing develops the gluten in the flour too much, which can result in cookie bars that are more cakey and fluffy instead of wonderfully chewy and rich. Mix just until the ingredients are combined and no streaks of flour remain.
• Avoid Overbaking at All Costs: Just like with brownies, overbaking recipes that contain cocoa powder can lead to a dry, crumbly texture and an unpleasantly bitter flavor. Keep a close eye on your oven; ovens vary, so while mine is perfect at 15 minutes in a light-metal 9×13 pan, yours might need slightly more or less time. Look for the center to be just set but still a little soft – a slight jiggle is okay! Trust me, slightly underbaked is better than overbaked for fudgy bars.
• Get Creative with Chocolate Chips & Mix-ins! These double chocolate cookie bars are a fantastic canvas for experimentation.
  • Chocolate Variety: Besides semi-sweet, try a blend of white chocolate chips for a sweet contrast, milk chocolate chips for a milder flavor, or dark chocolate chunks for an even more intense chocolate hit.
  • Candy & Nuts: Mini M&M’s, chopped Reese’s peanut butter cups, toffee bits, or even a sprinkle of chopped walnuts or pecans can add extra flavor and texture.
  • Triple Chocolate Bars: Combine two or three different types of chocolate chips (e.g., semi-sweet, white, and milk chocolate) to create a truly decadent “triple chocolate” experience.
• Finish with Flaky Sea Salt: The internet (especially TikTok!) loves flaky sea salt on chocolate for a reason! A delicate sprinkle of flaky sea salt on top of the warm, just-out-of-the-oven bars enhances the chocolate flavor beautifully and adds a delightful pop of savory crunch. It’s a simple touch that truly elevates the experience.
• Transform into a Decadent Cookie Cake: This recipe is essentially a larger, more intense version of my popular triple chocolate cookie cake. If you’re looking to turn these bars into a festive rectangular cookie cake in a 9×13 pan, you can easily adapt the frosting recipe from my cookie cake post. Just remember to double the frosting recipe to create a generous and beautiful border for your cake.
• Measure Flour Correctly: For consistent results, always spoon your flour into the measuring cup and then level it off with a straight edge. Scooping directly with the measuring cup can compact the flour, leading to using too much and potentially dry bars.

Frequently Asked Questions About Double Chocolate Chip Cookie Bars:

How to Store & Freeze These Cookie Bars?

• Storing: To maintain their optimal freshness and softness, cover the pan tightly with plastic wrap or transfer the cut bars into an airtight container. Store them at room temperature for up to 2-3 days. While they are still enjoyable on day 3, they are truly at their best within the first two days, before they begin to dry out.
• Freezing: These double chocolate cookie bars freeze wonderfully! First, ensure the bars are completely cooled to room temperature. Then, you can either freeze them as a whole slab (if you plan to serve a large crowd later) or slice them into individual squares. Place them in a single layer in an airtight freezer-safe container or a heavy-duty freezer bag, with parchment paper between layers if stacking. They will keep well in the freezer for 1-2 months. When ready to enjoy, simply thaw them at room temperature. Do note that cocoa powder-based cookies can sometimes experience a slight change in texture when frozen for extended periods, tending to dry out a bit more quickly than other types of cookies.

Can I Make These Double Chocolate Cookie Bars Gluten-Free?

I haven’t personally tested this specific recipe using gluten-free flour, so I cannot guarantee the exact results. However, many readers have had success substituting all-purpose flour with a good quality 1-to-1 gluten-free baking flour blend. My favorite brand for gluten-free baking is Bob’s Red Mill Gluten-Free 1-to-1 Baking Flour. If you decide to give it a try, please report back on your experience! Keep in mind that gluten-free flours can absorb liquids differently, so the dough consistency might vary slightly, and you might need to adjust baking time by a minute or two.

How Do You Achieve Such Cleanly Cut Cookie Bar Squares?

Achieving perfectly clean cuts on your double chocolate chip cookie bars is easier than you think with a couple of simple tricks! First, it is absolutely essential to let the bars cool completely – ideally for several hours or even chilling them in the refrigerator for about 20-30 minutes before slicing. This allows the chocolate chips and the bars themselves to firm up, preventing crumbling and smearing. Second, use a large, sharp, straight-edged knife. For the ultimate clean cut, wipe your knife blade clean with a warm, damp cloth or paper towel between each slice. This removes any melted chocolate residue, ensuring each square has crisp, defined edges.

Why Are My Cookie Bars Dry or Cakey Instead of Fudgy?

There are typically two main culprits for dry or cakey cookie bars: overmixing the dough and overbaking. Overmixing develops too much gluten in the flour, leading to a tougher, more cake-like texture. Mix only until the ingredients are just combined. Overbaking, on the other hand, dries out the moisture in the bars, resulting in a crumbly texture and potentially a bitter chocolate flavor. Remember to pull them from the oven when the center is just set but still looks a little soft; they will continue to cook and firm up as they cool.