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There’s something universally nostalgic about the combination of cookies and colorful M&M’s. These Classic M&M Cookie Bars bring together the comforting taste of homemade cookies with the cheerful crunch of M&M’s, all packed into thick, chewy bars that are perfect for sharing—or keeping all to yourself. Unlike traditional drop cookies, cookie bars offer a quicker way to whip up a batch of treats without the fuss of rolling dough or baking multiple trays.

This recipe starts with a buttery, rich dough made from pantry staples, then gets loaded with mini chocolate chips and M&M’s for extra texture and chocolatey bursts in every bite. Whether you’re baking for a birthday party, a school event, or just a cozy night in, these bars are a guaranteed hit. They’re also a great recipe to get kids involved in the kitchen—fun to make and even more fun to eat.

Best of all, these bars are adaptable: you can easily tweak them to match a holiday theme, adjust the sweetness, or swap in your favorite candy. Simple, satisfying, and sure to please everyone, these cookie bars deserve a spot in your dessert rotation.

Why You’ll Love This Recipe

Quick and Easy – No need to scoop individual cookies; just press the dough into a pan and bake.
Perfect for Crowds – Makes a large batch that’s ideal for parties, potlucks, or school lunches.
Fun and Colorful – The M&M’s add a pop of color and crunch that make these bars visually irresistible.
Customizable – Easily swap in different candies, chocolate chips, or mix-ins for seasonal or personal preferences.
Chewy and Buttery Texture – Thick, soft centers with crisp edges—everything you want in a cookie bar.

Ingredients

Unsalted butter
Granulated sugar
Golden brown sugar
Eggs
Pure vanilla extract
All-purpose flour
Baking soda
Salt
M&M’s
Mini chocolate chips

Variations

Holiday Theme: Use seasonal M&M’s (red and green for Christmas, pastel for Easter, etc.) to match any occasion.
Nutty Crunch: Add chopped walnuts or pecans for an extra layer of flavor and crunch.
Peanut Butter Twist: Swirl in peanut butter or use peanut butter M&M’s for a richer taste.
Gluten-Free: Use a 1:1 gluten-free baking flour to accommodate dietary needs.
Extra Chocolate: Drizzle melted chocolate over the cooled bars for an indulgent touch.

How to Make the Recipe

Step 1: Preheat and Prepare

Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking pan or line it with parchment paper for easy removal.

Step 2: Cream the Butter and Sugars

In a large bowl, beat the room-temperature butter with the granulated sugar and brown sugar until light and fluffy.

Step 3: Add Eggs and Vanilla

Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.

Step 4: Combine Dry Ingredients

In a separate bowl, whisk together the flour, baking soda, and salt.

Step 5: Mix Wet and Dry

Gradually add the dry ingredients to the wet mixture, mixing until just combined.

Step 6: Fold in Candy and Chips

Gently fold in the M&M’s and mini chocolate chips, reserving some for topping.

Step 7: Transfer to Pan

Spread the dough evenly into the prepared baking pan. Press the reserved M&M’s and chocolate chips on top for a bakery-style finish.

Step 8: Bake

Bake for 30–35 minutes or until the top is golden and a toothpick inserted into the center comes out clean or with a few moist crumbs.

Step 9: Cool and Slice

Allow to cool completely in the pan before slicing into bars.

Tips for Making the Recipe

Use room temperature ingredients for smoother mixing and even baking.
Don’t overmix once the flour is added—this keeps the bars soft and tender.
Line your pan with parchment paper for easy lifting and cleaner slices.
For thicker bars, use a slightly smaller pan and adjust the baking time accordingly.
Add a pinch of sea salt on top after baking for a sweet-and-salty finish.

How to Serve

These cookie bars are best served slightly warm with a glass of milk or a scoop of vanilla ice cream. They also make a fun addition to dessert platters or cookie exchanges. For parties, cut them into bite-sized squares and serve on decorative trays.

Make Ahead and Storage

Storing Leftovers

Store cooled cookie bars in an airtight container at room temperature for up to 5 days. They’ll stay soft and chewy!

Freezing

Wrap bars individually or store in a freezer-safe container with parchment between layers. Freeze for up to 2 months. Thaw at room temperature before serving.

Reheating

Microwave a bar for 10–15 seconds to restore that fresh-baked warmth and softness.

FAQs

1. Can I use regular-sized chocolate chips instead of mini?

Yes, but mini chips distribute more evenly throughout the dough.

2. What type of M&M’s work best?

Classic milk chocolate M&M’s are perfect, but you can also use peanut, crispy, or seasonal varieties.

3. Can I double this recipe?

Absolutely! Just use a larger pan or bake in two batches.

4. How do I know when the bars are done?

Look for a golden top and a toothpick that comes out mostly clean with a few moist crumbs.

5. Can I reduce the sugar?

You can slightly reduce the sugar, but it may affect the texture and chewiness.

6. What if I don’t have parchment paper?

You can grease the pan well with butter or cooking spray, but parchment makes removal easier.

7. Can I use a hand mixer instead of a stand mixer?

Yes, a hand mixer works well for this recipe.

8. How thick should the dough layer be in the pan?

Spread it evenly—it should be about 1 inch thick for even baking.

9. Can I make these bars gluten-free?

Yes, just substitute a 1:1 gluten-free flour blend.

10. Can I add other candies or mix-ins?

Definitely! Try chopped candy bars, white chocolate chips, or crushed pretzels.

Conclusion

Classic M&M Cookie Bars are a timeless, crowd-pleasing treat that combines buttery cookie dough with the crunch and color of M&M’s. They’re easy to prepare, fun to customize, and make the perfect sweet addition to any occasion. Whether you’re baking for loved ones or simply satisfying a craving, this recipe is one you’ll return to again and again. Make a batch today and enjoy the chewy, chocolatey joy in every bite.