These Halloween Cookie Bars are an easy and fun recipe filled with Oreos and M&Ms. Top with some sprinkles and you have a fun festive treat.

Stacked Halloween Cookie Bars on white surface with Halloween decor in background.

Halloween is just around the corner and what fun is Halloween without all the fun baked goods?

I mean you get all the candy trick-or-treating if you have kids, but how about adults?

Welcome these Halloween Cookie Bars, these are great for both kids and adults alike, but while the kids get their candy we get these yummy Cookie Bars.

Made with simple and easy pantry ingredients, they are a fun bar recipe that you can throw together in no time! I love easy and simple recipes and this one is just that.

Plus all the fun colors for Halloween, how could you not want to make these. They are fun, but they are oh so tasty too! Cookie Bars are one of my favorite desserts!

I love creating fun and colorful desserts for the holidays and these are ones that I like to make every year! They go quickly, so be prepared for that.

These are also fun to make with the kids, if you are in the Halloween baking mood These Halloween Cookie Bars are the perfect easy recipe to get those little hands to help with!

Some of my other favorite bar recipes that I have on my site include: Hello Dolly Bars, Brookies and Lunch Lady Peanut Butter Bars.

Overhead of finished bars cut showing Oreo's, M&Ms and sprinkles.

WHY THIS RECIPE WORKS:

With easy to find ingredients these come together super quick!
You can make these all year long, switching out the sprinkles and M&Ms for every holiday!
This makes a large batch so they are great to bring to any of your gatherings.

INGREDIENTS NEEDED (FULL RECIPE AT THE BOTTOM OF THE POST):

All-purpose flour
Kosher salt
Baking soda
Unsalted butter
Granulated sugar
Light brown sugar,
Eggs
Vanilla extract
Halloween colored M&Ms (or Cookies and Cream flavored)
Oreos
Sprinkles

Ingredients needed to make Halloween Cookie Bars.

Preheat the oven to 350 degrees F. Line a 9×13-inch baking pan with parchment paper, set aside.
In a large bowl, whisk together the flour, salt, and baking soda, set aside.
In the bowl of a stand mixer, beat together the butter granulated sugar and brown sugar until combined.
Add in the eggs and vanilla and beat well, making sure to scrape down the sides.
Slowly add in flour mixture, and mix until everything is just combined.
Fold in 1 cup each of M&Ms and chopped Oreos.
Evenly spread the batter into the prepared pan pushing down the top slightly, then top with remaining M&Ms, Oreos, and sprinkles.
Bake for 24 to 27 minutes until the edges are just turning a golden brown.
Remove from the oven and let the bars cool in the pan completely.
Take the bars out of the pan using the edges of the parchment to pull and cut into squares.

Step by step photos on how to make Halloween Cookie Bars.

CAN I DOUBLE THIS RECIPE FOR A PARTY OR LARGER CROWD?

Yes absolutely! Since the original recipe is made in a 9×13-inch pan which is great for a family or a small crowd, you can absolutely make more of these and I highly recommend it.

Just double all the ingredients called for in the recipe and then place in a lined 13×18-inch pan. The higher the sides the better, but these usually come standard with 1″ sides.

If you don’t want to use a larger pan, you can just make these in 2 9×13-inch pans and the cut and stack on a nice serving platter!

My recommendation for keeping any bars soft is once they are cooled, cut them and immediately put into an airtight container or bag.

You can store in the pan if you tightly wrap with foil, you just want to make sure that no air hits the sides of the bars where they would get dry.

These are a fun and tasty combination of cookies and cream and chocolate in a sweet bar.

Some things that could be added include chopped nuts, candy corn, chocolate chips, white chocolate chips, candy pieces, etc. When it comes to cookie bars there really is tons of options.

Since we went the Halloween route with this we really liked the combination or colors that we used! Trust me they are absolutely amazing this way, but the base recipe is great to build off of.

WHAT KIND OF M&MS SHOULD I USE?

We have previously used the Cookies and Screeem M&Ms for this recipe (cookies and cream flavored), but some stores do not carry them but you can find them online and at some stores.

Any Halloween colored M&Ms will work perfectly fine for this recipe and the flavor will still be amazing.

You can switch it up and try using different flavors that go well with Oreos such as peanut butter, crispy, mint, etc.

If you want to stick with the theme, make sure that you are using Halloween colored M&Ms.

Overhead stacked Cookie Bars on black plate.

HOW TO STORE:

These can be stored in an airtight container or bag where they will keep at room temperature for about 3-5 days.

You can also freeze these Cookie Bars. Make sure you bars are cooled and then you can cut them. We like to individually wrap each bar in plastic wrap and place in a freezer bag where they will keep for up to 3 months.

To defrost, remove from freezer and let defrost on countertop until thawed.

TIPS AND TRICKS:

These are somewhat thicker, so I do not recommend using anything smaller than the 9×13-inch pan.
You can absolutely double these bars and either make in two 9×13-inch pans or a 13×18-inch pan.
If you can’t find the Cookies and Cream M&Ms you can use other Halloween colored M&Ms.
Switch up the colors of sprinkles and M&Ms for each holiday!
The base is great to build off of and you can add anything you like to it, see my tips above.
These can be frozen, again see above on how to do that.
Make these with kids for a fun holiday treat.
Make sure that you fully cool in the pan before cutting.

Close up of stacked bars on plate, side view with black house in background.

Want a colorful, fun and not to mention super easy recipe for the upcoming spooky holiday? Then you need to make a batch of my Halloween Cookie Bars!

If you like this recipe you might also like:

If you’ve tried these HALLOWEEN COOKIE BARS or any other recipe on my site, let me know in the comment section how it turned out, we love hearing from our readers! You can also follow along with me on PINTEREST, FACEBOOK and INSTAGRAM to see more amazing recipes and what shenanigans I’m getting into!

ORIGINALLY POSTED OCTOBER, 2021