Introduction
If you’re looking for a dessert that’s colorful, chewy, and guaranteed to impress, M&M’s Halloween Cookie Bars are the treat you need this spooky season. Unlike cut-out cookies that require rolling and shaping, these Halloween cookie bars bake in one pan, slice neatly, and deliver big flavor with minimal effort. Packed with chocolate chips, festive sprinkles, and candy-coated M&M’s, they’re everything you want in an easy Halloween dessert bar—fun, festive, and crowd-pleasing.
These chewy bars are a cross between a chocolate chip cookie and a brownie, with buttery edges, a soft center, and a crunch of seasonal candy in every bite. They’re a great option if you’re short on time but still want to contribute a stunning dessert to your Halloween party dessert table. Whether you’re baking for a class party, trick-or-treat night, or a cozy family gathering, M&M’s Halloween Cookie Bars will disappear fast—and leave everyone asking for the recipe.
Table of Contents
Why You’ll Love This Recipe
M&M’s Halloween Cookie Bars are the kind of treat that check every box for busy families and party hosts. They’re quick to make, full of chocolatey goodness, and festive enough to be the highlight of any dessert table. Here’s why they deserve a spot in your Halloween baking rotation:
- Quick and family-friendly – No need to roll, chill, or cut shapes like with traditional cookies. Just press the dough into a pan, bake, and slice into chewy, colorful bars. Perfect for baking with kids.
- Perfect Halloween party dessert – Whether you’re hosting a haunted house, class party, or potluck, these Halloween dessert bars serve a crowd and look fantastic on a platter.
- Packed with chocolate and color – Loaded with chocolate chips, Halloween M&M’s, and sprinkles, each bite delivers gooey sweetness and festive crunch.
- Versatile for gatherings – From bake sales to trick-or-treat night, these chewy bars travel well, hold their shape, and disappear fast.
If you’re planning a bigger celebration, pair these bars with a Spooky Halloween Charcuterie Board to wow guests with a spread of sweet and savory bites. Together, they create the ultimate Halloween party lineup.
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M&M’s Halloween Cookie Bars
- Total Time: 45 minutes
- Yield: 20 bars 1x
Description
These M&M’s Halloween Cookie Bars are soft, chewy, and loaded with festive chocolate candies. Easier than cut-out cookies but just as colorful, they’re the ultimate Halloween dessert bars for parties, bake sales, or family fun.
Ingredients
- 2 sticks unsalted butter, at room temperature
- 1 cup granulated sugar
- 1 cup firmly packed golden brown sugar
- 3 large eggs, at room temperature
- 1 ½ teaspoons pure vanilla extract
- 3 cups all-purpose flour, spooned and leveled
- ¾ teaspoon baking soda
- ¾ teaspoon salt
- 1 ½ cups Halloween M&M’s, plus more for topping
- 1 cup mini chocolate chips, plus more for topping
Instructions
- Preheat oven to 350°F (175°C). Line a 9×13-inch baking pan with foil, leaving overhang for easy removal. Spray with nonstick cooking spray.
- In the bowl of a stand mixer, beat butter, granulated sugar, and brown sugar together until light and fluffy.
- Add eggs and vanilla extract. Mix until well combined.
- Lower mixer speed and add flour, baking soda, and salt. Mix until just incorporated.
- Fold in M&M’s and mini chocolate chips, reserving some for topping.
- Transfer dough to prepared pan and spread evenly. Press reserved M&M’s and chocolate chips into the top.
- Bake for 30–35 minutes, or until golden brown and set in the center.
- Cool completely in pan before lifting out with foil and cutting into squares.
Notes
- For even chewier bars, slightly underbake and let them finish setting as they cool.
- Swap in peanut butter or caramel M&M’s for fun flavor twists.
- Store leftovers in an airtight container at room temperature for up to 4 days.
- Freeze bars tightly wrapped for up to 2 months.
- Prep Time: 15 minutes
- Cook Time: 30 minutes
- Category: Dessert
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1 bar
- Calories: 171 kcal
- Sugar: 22 g
- Sodium: 123 mg
- Fat: 3 g
- Carbohydrates: 34 g
- Fiber: 1 g
- Protein: 3 g
- Cholesterol: 22 mg
Key Ingredients That Make These Bars Stand Out
What makes M&M’s Halloween Cookie Bars so irresistible is the balance of classic chocolate chip cookie dough with festive add-ins that make them perfect for spooky season. Let’s break down the essentials:
- Unsalted butter – Creates a rich, buttery base that gives these bars their soft, chewy texture. Make sure it’s at room temperature so it creams easily with the sugars.
- Granulated sugar + brown sugar – This duo adds sweetness and helps the bars bake up chewy in the center with lightly crisp edges. Brown sugar also brings a hint of caramel flavor.
- Eggs + vanilla extract – Eggs give structure, while vanilla adds warmth and enhances the sweetness. Use pure vanilla extract for the best flavor.
- All-purpose flour – Provides the structure needed to hold all the chocolate and candies without falling apart when sliced.
- Baking soda + salt – The baking soda gives just enough lift, and the salt balances the sweetness for a perfectly rounded flavor.
- Halloween M&M’s – The star ingredient. Their bright colors scream Halloween, and the candy-coated crunch makes each bite more fun.
- Mini chocolate chips – Melty pockets of chocolate that make these bars extra indulgent.
- Festive sprinkles – Optional, but highly recommended! They add more Halloween flair and make your bars stand out on a party table.
👉 Pro Tip: Want more inspiration for colorful Halloween treats? Check out these Halloween Sugar Cookies with Royal Icing. They’re another festive bake that pairs perfectly with these chewy bars.
Step-by-Step Instructions
Making M&M’s Halloween Cookie Bars is easier than it looks, and the process is beginner-friendly while still producing bakery-style results. Follow these steps for chewy, chocolate-packed bars every time:
Step 1: Prepare the pan and oven
Preheat your oven to 350°F (175°C). Line a 9×13-inch baking pan with aluminum foil, leaving a bit of overhang on the sides. This makes it easier to lift the bars out for clean slicing later. Lightly spray the foil with nonstick cooking spray or brush with melted butter.
Pro Tip: Using foil or parchment guarantees neat edges and prevents sticking—essential for pretty slices that stand out at bake sales or Halloween parties.
Step 2: Cream the butter and sugars
In a large mixing bowl, beat together unsalted butter, granulated sugar, and brown sugar until light and fluffy. This step usually takes 2–3 minutes with a hand or stand mixer. The mixture should look pale and slightly whipped.
Why this matters: Creaming introduces air into the dough, giving these bars their signature soft, chewy texture instead of being too dense.
Step 3: Add eggs and vanilla extract
Beat in the eggs one at a time, scraping the bowl between additions to ensure even mixing. Stir in the vanilla extract for flavor depth.
Pro Tip: Room-temperature eggs incorporate more smoothly into the dough, creating a cohesive batter that bakes evenly.
Step 4: Mix in the dry ingredients
In a separate bowl, whisk together all-purpose flour, baking soda, and salt. Slowly add the dry mixture into the wet ingredients, mixing on low speed until just combined.
Avoid overmixing here—it can develop too much gluten and make your cookie bars tough instead of chewy.
Step 5: Fold in the candy and chocolate
Gently fold in the Halloween M&M’s and mini chocolate chips, reserving a small handful of each for topping. This ensures the candies are distributed throughout the dough, so every bite is loaded with chocolatey crunch.
If you want to add extra flair, mix in a sprinkle of orange, purple, and black jimmies for even more festive Halloween vibes.
Step 6: Press the dough into the pan
Spread the dough evenly into your prepared pan. Use a spatula or the back of a spoon to smooth out the top. Press the reserved M&M’s and chocolate chips gently onto the surface—this not only makes the bars prettier but also guarantees chocolatey bites in every square.
Pro Tip: For thicker, bakery-style cookie bars, chill the filled pan in the refrigerator for 15 minutes before baking. This helps the dough set and prevents spreading.
Step 7: Bake to perfection
Bake at 350°F for 30–35 minutes, or until the edges are golden brown and the center looks set but slightly soft. A toothpick inserted near the center should come out with a few moist crumbs.
Be careful not to overbake—the residual heat will continue cooking the bars in the pan as they cool.
Step 8: Cool and slice
Allow the M&M’s Halloween Cookie Bars to cool completely in the pan before lifting them out with the foil overhang. Use a sharp knife to slice into squares or rectangles.
These chewy, colorful bars slice cleanly and hold their shape beautifully, making them ideal for Halloween dessert bars at parties, school events, or potlucks.
Extra Tips for Success
- Storage: Keep bars in an airtight container at room temperature for up to 5 days. For longer storage, freeze for up to 2 months.
- Customization: Swap in peanut butter M&M’s, caramel chips, or white chocolate chips for fun flavor twists.
- Party hack: Drizzle melted chocolate over the cooled bars and sprinkle with more festive sprinkles before serving for extra Halloween magic.
- Optional finish for bakery look: After the M&M’s Halloween Cookie Bars cool, drizzle thin ribbons of melted white chocolate over the top, then add a pinch of festive sprinkles. If you love that candy-studded sheen, you’ll also like my easy White Chocolate Halloween Bark—it’s a quick companion for any Halloween dessert bars tray.
Variations & Customization Ideas
The beauty of M&M’s Halloween Cookie Bars is how versatile they are. With just a few swaps or tweaks, you can create new versions that suit your taste, dietary needs, or the theme of your Halloween celebration. Here are some fun ways to make them your own:
1. Gluten-Free Halloween Cookie Bars
Swap the all-purpose flour for a 1:1 gluten-free flour blend. Be sure it contains xanthan gum for structure, otherwise your bars may crumble. These gluten-free versions are still chewy, chocolatey, and festive—perfect for serving at a party where guests may have dietary restrictions.
2. Peanut Butter Twist
Replace half the butter with creamy peanut butter for rich, nutty cookie bars. pair these bars with bright, kid-favorite Halloween Sprinkle Cookies or Reese’s Pieces for an indulgent take on classic Halloween dessert bars. This version is especially popular for bake sales, since peanut butter lovers will snatch them up quickly.
3. White Chocolate & Candy Corn Bars
For a fun seasonal spin, fold in white chocolate chips and candy corn instead of mini chocolate chips. The result is a softer, sweeter version of these easy Halloween dessert bars, with a nostalgic candy flavor.
4. Monster Cookie Bar Version
Turn these into spooky Halloween treats by adding candy eyes on top as the bars come out of the oven. Kids especially love this playful twist, and they make a big statement on a Halloween party dessert table.
5. Holiday Crossover Bars
Love the recipe but want to use it beyond Halloween? Swap the festive M&M’s and sprinkles for red and green at Christmas, pastel at Easter, or red, white, and blue for the Fourth of July. These bars are endlessly adaptable for any holiday gathering.
6. Single-Serve Bars
If you want a party-friendly serving option, bake the dough in a muffin tin for individual cookie bars. These bake up faster and look adorable topped with a dollop of whipped cream or a drizzle of melted chocolate.
By exploring these variations, you’ll see just how flexible M&M’s Halloween Cookie Bars can be. Whether you’re baking for a classroom party, a neighborhood gathering, or just a cozy night in, you can adjust this recipe to fit the occasion perfectly.
FAQs About M&M’s Halloween Cookie Bars
Why are my cookie bars dry instead of chewy?
Dry cookie bars usually mean too much flour was added or they were overbaked. Always measure flour using the spoon-and-level method or a digital scale for accuracy. Pull the bars out of the oven when the center looks slightly underdone—they’ll finish baking as they cool, resulting in chewy Halloween dessert bars.
Can I make Halloween cookie bars ahead of time?
Yes! These bars are perfect for make-ahead baking. You can prepare the dough up to 48 hours in advance and refrigerate it until ready to bake. Baked bars store well in an airtight container for 3–4 days at room temperature, and they freeze beautifully for up to 2 months. Just thaw overnight before serving at your Halloween party dessert table.
Can I use regular M&M’s instead of Halloween-themed ones?
Absolutely. While Halloween M&M’s add festive colors, the recipe works just as well with any variety—classic milk chocolate, peanut butter, or even caramel M&M’s. For the most seasonal look, though, the orange, purple, and green candies make your M&M’s Halloween Cookie Bars instantly recognizable as a spooky-season dessert.
What’s the best way to cut cookie bars neatly?
Allow the bars to cool completely before slicing. Use a sharp knife dipped in hot water, then wipe clean between cuts for the cleanest edges. If you want bakery-style presentation, chill the bars briefly in the fridge before cutting.
Can I make these cookie bars nut-free?
Yes! This recipe is naturally nut-free, as it uses regular chocolate chips and M&M’s. Just make sure to double-check the candy packaging, as some varieties of M&M’s may be produced in facilities that process nuts.
Conclusion
When it comes to festive baking, M&M’s Halloween Cookie Bars are the ultimate crowd-pleaser. They combine the chewiness of a classic chocolate chip cookie with the fun, colorful crunch of seasonal candy. Easier than rolling or shaping cookies, these Halloween dessert bars bake in a single pan, slice beautifully, and bring instant cheer to any party table.
Whether you’re planning a classroom treat, stocking a Halloween bake sale, or building out a Halloween party dessert table, these cookie bars fit right in. Packed with chocolate chips, festive M&M’s, and just the right amount of sweetness, they’re a dessert that disappears quickly—and leaves everyone asking for seconds.
The best part? They’re endlessly customizable. Swap in peanut butter candies, add candy eyes for spooky fun, or drizzle with white chocolate for a bakery-style finish. No matter how you make them, these bars guarantee smiles with every bite.
So preheat your oven, grab a bag of festive M&M’s, and bake up a batch of M&M’s Halloween Cookie Bars. They’ll quickly become a staple in your holiday baking—and a recipe you return to every Halloween season.