Easy Dirt Cookie Bars

These thick, fudgy, brownie-like cookie bars are a take on the nostalgic dirt dessert! Chocolate + OREOS + gummy worms = a summertime dream.

Save this Recipe!

Enter your email below and I'll send this recipe to you.

Click Here to Pin this Recipe for Later!

Why I Love These Easy Dirt Cookie Bars

Fudgy & brownie-like: They use an adapted version of my fudgy cosmic brownie cookie recipe but made thicker for a 9x13 pan!
Easy to make cookies: No scooping of cookies needed!
Perfect for a crowd: I just love a good pan of 9x13 cookie bars because you can cut them into 12 large squares, 24 smaller squares, or even cut each of those squares in half for 48 cookie sticks!

Ingredient Notes & Substitutions

Cocoa Powder: I use and recommend Hershey’s Special Dark Cocoa powder to give them a moist, rich flavor. You can substitute for regular unsweetened cocoa powder, just note that your cookies will have a puffier texture and won’t have the iconic brownie taste.
OREOs: We're using Oreo crumbs inside the dough & on top for that iconic dirt dessert flavor.
Gummy Worms: I recommend a *soft* gummy worm like Albanese rather than a super chewy brand, as they'll be easier to cut and eat.
Light Corn Syrup: We’re using a small amount of corn syrup to create a chewy, dense, fudgy cookie.

How to Make Dirt Cookie Bars

Step 1: Crush Oreos

Place 12 OREOs in a large ziploc bag and use a rolling pin to crush into fine crumbs (or use a food processor). This amount will give you enough for the dough & topping.

Step 2: Make Dough

In a large bowl, use an electric mixer to mix together cookie dough. The dough will be a bit thick and sticky, as shown below.

Preheat oven to 350°F.
In a large bowl, use an electric mixer on medium-high speed to cream softened unsalted butter (¾ cup, 1 ½ sticks), light brown sugar (¾ cup), and granulated sugar (¾ cup) for 2 minutes until light and fluffy.
Add the eggs (2 large), vanilla extract (2 teaspoons), and light corn syrup (3 tablespoons) and mix on low speed until combined. Scrape down the sides of the bowl so everything can combine.
Add in baking powder (1 teaspoon) and salt (½ teaspoon) and mix for another 5-10 seconds until combined.
Lastly, add dark cocoa powder (¾ cup), oreo crumbs (¾ cup), and all-purpose flour (2 ¼ cups) and mix on medium until combined.

Tip: Using softened butter is important here! If your butter is straight from the fridge, microwave for 10 seconds to slightly soften.

kitchenaid paddle with thick chocolate cookie dough

Step 3: Press Into Pan & Bake

Spray a light-colored metal 9×13 pan with cooking spray, then line the pan with parchment paper, leaving a 2-inch overhang on each long side so that you will be able to lift the bars out of the pan.

Drop the dough into 1-tablespoon-sized chunks into the prepared pan and spread until smooth on top. Bake bars at 350°F for 16-20 minutes, or until the center no longer looks wet. The center may look a tiny bit underdone but the bars will continue to bake in the hot pan when cooling. Allow to fully cool before decorating.

Tip: This dough is a little sticky, so to help spread, I recommend spraying your hands with cookie spray or placing another piece of parchment paper on top and continuing to press down.

raw chocolate cookie dough pressed into 9x13 metal pan

baked chocolate cookie dough pressed into 9x13 metal pan

Step 4: Make Frosting

In a large microwave-safe mixing bowl, beat the softened unsalted butter (½ cup, i.e. 1 stick), vanilla extract (2 teaspoons), and salt (¼ teaspoon) on medium-high speed for 1 minute until smooth.
Turn the mixer to low speed then slowly add the dark cocoa powder (3 tablespoons) and powdered sugar (1 cup). You may need to stop and scrape down the sides. Add 1 tablespoon of milk.
Microwave for 10 seconds, then stir to make glossy & easy to spread.

Step 5: Decorate & Drizzle

Spread frosting over cooled cookie bars. Top with remaining ¼ cup OREO crumbs and gummy worms.

dirt dessert cookie bars in a pan with gummy worms on top

Step 6: Cut

Allow chocolate to harden before cutting; it's best to refrigerate or freeze for 30 minutes to help set.

Tip: To get clean slices, fill a tall cup with hot water. In between cuts, dip the knife into the water and use a paper towel to dry it off. When cutting, don't "saw" the bars but rather press straight down and gently lift the knife.

Tips & Variations

Chop the gummy worms! To make them easier to cut & eat, cutting the gummy worms in little "sprinkles" is a good idea!
Cut them into small squares or sticks! While you can cut these into 12 large squares, I think the smaller 24-square size is perfect for these. Or if you want to serve up bite-sized pieces, cutting each of those squares into 2 "sticks" will get you 48 scrumptious bites!

Frequently Asked Questions:

Can I omit the corn syrup?

When I was first creating this base dough for the fudgy cosmic brownie cookies, I found that you just can’t achieve the dense, fudgy texture without a tiny bit of corn syrup. In addition, the corn syrup adds sweetness to the cookie without adding more granulated sugar which can give it a gritty texture. I promise it’s worth it!

If you don’t want to use it or can’t find it where you live, you can use thick honey or light molasses to achieve a similar texture (it won’t be exact). Or you can use 1 tablespoon of milk but keep note that the cookies will likely end up puffier and won’t have the same chewy, dense, fudgy texture.

Can I use regular cocoa powder?

You can, just keep in mind that you won’t have as moist, rich, and fudgy of a cookie bar (I find that the dark cocoa powder really does make a difference in moistness!). Regular unsweetened cocoa powder is more acidic and will react with the baking soda, creating a puffier cookie.

Do I need to refrigerate these?

Aside from chilling them to help the frosting harden to cut, you don't need to refrigerate them and you can simply store them in an airtight container.

Did you make this recipe? If so, will you do me a huge favor and leave a review and rating letting me know how you liked this recipe? This helps my small business thrive so I can continue providing free recipes and high-quality content for you.