Loaded M&M Oreo Cookie Holiday Bars


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Loaded Holiday M&M’s Cookie Bars — These M&M’s cookie bars are packed with holiday M&M’s and crushed Oreos. This is an easy, one-bowl holiday dessert your family will love! 

stack of four oreo and M&M's Cookie Bars

Loaded Christmas Bar Cookies

These M&M’s cookie bars are famous. Well, maybe not these exact bars but the original recipe is. The original recipe has been Pinned over 1 million times and appeared on the cover of Taste of Home Magazine in 2014.

I made the original recipe on a whim because I was moving and had a half package of both Oreos and M&M’s open, didn’t want to move them, didn’t want to toss them, made the bars, and the rest is history.

This cookie bars recipe is a spinoff on my trusty blondie base. When I want an easy, fuss-free, one-bowl, no-mixer recipe that I know everyone will love, it’s my go-to. With 30+ versions and counting, it never lets me down.

It’s an easy recipe to memorize because everything is ‘one’. In the 1 bowl used, melt 1 stick of butter, stir in 1 egg, 1 cup of brown sugar, 1 tablespoon vanilla, 1 cup flour. For this version, there’s Oreos and M&M’s added.

I was on the hunt for red or green-filled seasonal Oreos but was just a bit too early when I made the bars a few weeks back. I think mint M&M’s or mint Oreos would be a great touch here as well.

These M&M’s cookie bars are loaded with goodies in every bite. Crunchy Oreos and crisp M&M’s are a great texture contrast to the soft, buttery bars.

M&M's Cookie Bar surrounded by holiday M&M's

What’s in M&M’s Cookie Bars?

To make these easy cookie bars, you’ll need:

  • Unsalted butter
  • Egg
  • Brown sugar
  • Vanilla extract
  • All-purpose flour
  • Salt
  • Oreo cookies 
  • M&M’s

stack of oreo and M&M's Cookie Bars

How to Make M&M’s Cookie Bars

Melt the butter, then stir in the egg, vanilla, and brown sugar. Stir in the dry ingredients, then gently fold in the M&M’s and chopped Oreos. 

Turn the batter into a greased 8×8-inch baking dish and bake until the top is set in the center and done. The toothpick test is a bit tricky because there aren’t many bare batches, but if you hit a patch of just dough, the toothpick should come out clean, or with a few moist crumbs, but no batter.

Place pan on a wire rack to cool for at least 90 minutes before slicing and serving.

Want to see how to make cookie bars? Watch the video! 

Can I Add Other Mix-Ins? 

Of course! You can add other chopped holiday candies and chocolates to these M&M’s cookie bars. 

Can I Double This Recipe? 

Yes, simply double the ingredients and bake these cookie bars in a 9×13-inch pan. 

Loaded M&M Oreo Cookie Holiday Bars - Stuffed to the max with M&M's and Oreos!! Easy, no-mixer recipe that's ready in 30 minutes!! A guaranteed hit with everyone!!

Tips for Making M&M’s Cookie Bars

You just need to roughly chop the Oreos for these M&M’s cookie bars. You want them to be big enough to bite into, but not so big that you’re trying to chew half an Oreo at once. 

I made this recipe as Christmas bar cookies, but you can make these bars for any holiday. Just switch out the holiday M&M’s for whatever color you’d like. You can even add seasonal Oreos to the mix, if desired.

These M&M’s cookie bars can be kept on your counter for a few days, or you can pop them into a freezer bag and freeze them for later. They’re a great treat to have stashed in the freezer for last-minute guests this time of year! 

Loaded Holiday M&M's Cookie Bars — These M&M's cookie bars are packed with holiday M&M's and crushed Oreos. This is an easy, one-bowl holiday dessert your family will love! 

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Yield: 9 bars

Loaded M&M Oreo Cookie Holiday Bars

Loaded M&M Oreo Cookie Holiday Bars

These M&M's cookie bars are packed with holiday M&M's and crushed Oreos. This is an easy, one-bowl holiday dessert your family will love!

Prep Time 5 minutes
Cook Time 18 minutes
Cooling Time 1 hour 30 minutes
Total Time 1 hour 53 minutes


  • 1/2 cup unsalted butter (1 stick), melted
  • 1 large egg
  • 1 cup light brown sugar, packed
  • 1 tablespoon vanilla extract
  • 1 cup all-purpose flour
  • 1/2 teaspoon salt, or to taste
  • 18 Oreo cookies, roughly chopped
  • 1/2 cup M&M’s (I used Dark Chocolate Red and Green M&M’s)


    1. Preheat oven to 350F. Line an 8-by-8-inch baking pan with aluminum foil, spray with cooking spray; set aside.
    2. To a large, microwave-safe bowl add the butter and heat to melt, about 1 minute on high power.
    3. Wait momentarily before adding the egg so you don’t scramble it. Add the egg, brown sugar, vanilla, and whisk until smooth.
    4. Add the flour, salt, and stir until just combined, don’t overmix.
    5. Add the Oreos and stir to combine.
    6. Add the M&M’s and stir to combine.
    7. Turn the batter out into prepared pan, smoothing it lightly with a spatula and pushing it into the corners. Tip – Strategically place a few Oreos and M&M’s on top for visual appeal.
    8. Bake for about 18 to 21 minutes, or until top is set in center and done; don’t overbake. Bars firm up as they cool. A toothpick test is a bit tricky because there aren’t many bare batches, but if you hit a patch of just dough, the toothpick should come out clean, or with a few moist crumbs, but no batter.
    9. Place pan on a wire rack to cool for at least 90 minutes before slicing and serving.


  • Bars will keep airtight at room temperature for up to 1 week, or in the freezer for up to 6 months.
  • Recipe adapted from Loaded M&M's Oreo Cookie Bars.

Nutrition Information:



Serving Size:


Amount Per Serving: Calories: 394Total Fat: 18gSaturated Fat: 9gTrans Fat: 0gUnsaturated Fat: 4gCholesterol: 49mgSodium: 230mgCarbohydrates: 56gFiber: 1gSugar: 37gProtein: 3g

More Cookie Bars:

Holiday Sugar Cookie Bars with Cream Cheese Frosting — The bars are buttery soft in the middle with a bit of chewiness around the edges and have nice texture from the baked-in sprinkles.

Holiday Sugar Cookie Bars with Cream Cheese Frosting

Loaded M&M Oreo Cookie Bars — Stuffed to the max with M&Ms and Oreos! Easy, no-mixer recipe that’s ready in 30 minutes. Always a hit at parties!

Loaded M&M Oreo Cookie Bars - Stuffed to the max with M&Ms and Oreos! Easy, no-mixer recipe that's ready in 30 minutes. Always a hit at parties!

Snickerdoodle Bars with Cream Cheese Frosting — Snickerdoodle bars are so much FASTER AND EASIER than making snickerdoodle cookies!! The sprinkles and tangy cream cheese frosting will put everyone in the holiday spirit!!

Snickerdoodle Bars with Cream Cheese Frosting

M&M’S Chocolate Chip Cookie Bars — Soft buttery bars loaded with M&M’S and chocolate chips are a guaranteed hit! Fast, easy, foolproof, no mixer recipe that’s so much simpler than making cookies!

M&M’S Chocolate Chip Cookie Bars - Soft buttery bars loaded with M&M’S and chocolate chips are a guaranteed hit!! Fast, easy, foolproof, no mixer recipe that's so much simpler than making cookies!!

Triple Peanut Butter Monster Cookie Bars – Peanut butter is use 3 different ways! Peanut butter lovers will go nuts for these!

Triple Peanut Butter Monster Cookie Bars - Easy One-Bowl Recipe at averiecooks.com

Banana Oatmeal Chocolate Chip Cookie Bars — A FAST and EASY dessert that is on the HEALTHIER side with only 1/4 cup butter and no oil!! Bold banana flavor, chewiness from the oats, and plenty of chocolate in every bite!!

Banana Oatmeal Chocolate Chip Cookie Bars

Peanut Butter Chocolate Chip Bars — These peanut butter chocolate bars are loaded with chocolate chips and creamy peanut butter. This is a one-bowl dessert you’re bound to love!

Peanut Butter Chocolate Chip Bars 


About the Author

Welcome to AverieCooks! Here you’ll find fast and easy recipes that taste amazing and are geared for real life. Nothing fussy or complicated, just awesome tasting dishes everyone loves!

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Please note: I have only made the recipe as written, and cannot give advice or predict what will happen if you change something. If you have a question regarding changing, altering, or making substitutions to the recipe, please check out the FAQ page for more info.

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    3 1/4 cups all-purpose flour I sift flour for fuller results
    1 teaspoon baking soda
    1 teaspoon salt
    1 cup (2 sticks) butter, softened
    1 cup granulated sugar
    1 cup packed brown sugar
    1 teaspoon vanilla extract
    3 large eggs
    2 cups (12-oz. pkg.) NESTLÉ TOLL HOUSE Semi-Sweet Chocolate Morsels
    1 cup chopped nuts or reese’s optional you can add most any candy
    or crushed oreo’s

    PREHEAT oven to 350° F. Grease 11 X 13 cake pan

    COMBINE flour, baking soda and salt in small bowl. Beat butter, granulated sugar, brown sugar and vanilla extract in large mixer bowl. Add eggs, one at a time, beating well after each addition. Gradually beat in flour mixture. Stir in morsels and nuts. Spread into prepared pan.

    BAKE for 28 to 30 minutes or until golden brown. Cool in pan on wire rack. Cut into bars.

    Repost Freely Robert Thomas

  2. Hi Averie,

    I plan to make these tomorrow, but will be doubling the recipe and using a 13 x 9 pan. Did we reach consensus on the increased bake time, if any? I don’t want to screw them up. Would it be best to just split the batter into two 8 x 8 and use the recipe bake time?


    1. I don’t know if you will need to alter the baking time or not in a 9×13 pan. Just keep an eye on them and bake until done, whatever that time on the clock means or is. You won’t screw them up :)

  3. Wildly addictive and super easy to make. I always have to double the recipe. Making these for the third time this week. Everyone thinks I am a genius. Thanks, Averie!

    Rating: 5
    1. Thanks for the five star review and I’m glad that everyone thinks you’re a genius when you serve these!

  4. I made these over christmas and they were SO delicious!! everyone at work loved them!! all your recipes are so good :)

  5. I made these bars so many times this holiday season! Your blondie recipe is SO simple and yet absolutely delicious.
    Thank you so much for sharing.

    1. Thanks for trying the recipe and I’m glad it’s a favorite of yours! This basic blondie recipe of mine has been made into umpteen dozen concoctions but it always starts with this base – and I agree, simple yet delicious!

  6. Gee I made these a few times and the last couple times I cooked for 25 minutes and the batter was still uncooked in the middle. Uh please advise what to do the edges were getting too cooked.
    Thank you!

    1. All ovens and climates vary so it’s hard to say exactly. You could try laying a sheet of foil (tenting) your pan at the 20 minute mark or so and then baking until necessary. Will prevent top and sides from browning as much.

    2. Thank you! It’s strange I made two batches while at my daughters house in Texas they came out great cooked at 25 minutes. Came home to Massachusetts after Christmas made 4 batches and they all either stayed uncooked in centers or hard as rock if I cooked longer time. Ha ha I have yet another batch in oven right now! Will keep at it until I get them just right back here at home!

      1. That is strange but there is something to do with climate, exact material of the pan used, and/or ingredients (different flour comes to mind…they vary a lot from brand to brand). Glad you’re sticking with it. Keep me posted on how things go.

    3. Okay just out of the oven and they look browned with the center set just right!
      I baked 22 minutes, it wasn’t quite there so did am additional 3 minutes.
      I will now call it a success in my kitchen!
      I’m a determined cook and baker well known by my family to try a recipe till I perfect it!

  7. I made these last week and mailed them to a friend. They were a huge hit! These “mail” extremely well, in case anyone else needs to make cookies for mailing. The reason that I am commenting is that I noticed that over the past month, I have pinned and made a LOT of your recipes! Jeez, you would think that we were bffs or something! No worries about me being a bit too obsessive because I am a senior citizen! I have found all of your recipes to be delicious…many thanks.

    1. Thanks for all the pins and for making lots of my recipes! Glad to hear these ship well, too!

      I love that you’re baking lots, nothing wrong with that! Glad everything has been delicious!

  8. Love these cookie bars so yummy I made them but didn’t put them in the freezer and they came out really good but leave them to cool

  9. I made these but used the new cinnamon bun Oreos and cinnamon chips! They’re awesome! Very rich but very good. 

    1. Thanks for trying the recipe and glad it came out great for you! Fun twist with the cinnamon bun Oreos and cinnamon chips!

  10. These bars were fantastic and a HUGE hit at work and with the family over the holidays! One issue I had was that the bars ended up losing the “cookie batter” coloring once I crushed up the Oreos. So a few people thought they were brownies, due to their overall darker Oreo coloring. Do you have any suggestions for how to keep the Oreo from taking over the bar portion? Yours looks so neat and separate – mine looked like a jumbled mess! Of course, they were still delicious, but I am always trying to improve upon the visual appeal of my baking (which has always been a problem for me!). Thank you!! 

    1. Thanks for trying the recipe and glad it was a huge hit with everyone! To avoid the dough from looking ‘dirty’ from the Oreo pieces, don’t crush down the Oreos quite as much (less sandy crumbs) and if you do get lots of sandy crumbs, don’t add those to the dough. That’s the culprit and easy to solve.

  11. Could this be adjusted for a 9×13 pan? I have a cookie swap to attend and like to bring bars to save on time. Would you double the recipe and increase the baking time slightly?

      1. Thanks for trying the recipe and I’m glad it came out great for you as a double batch!

  12. I would love to make these, but I am wondering if there are any adjustments I would need to make for high altitude. We are at a little over 5,600 ft here.

    1. I don’t bake in altitude so can’t really say what you’d have to change or not change. It’s a very forgiving recipe so I say just make it as directed and hope for the best :) Or do what you’d normally do to recipes that are bars/blondies. The King Arthur Flour website has a great altitude adjustments tutorial if you google it.

    2. Made these with no adjustments and they were fabulous! I have a request for a second batch, so they will be going in the oven again this weekend!

  13. I just made these during my parent’s visit.  My mom put on her Christmas list ‘Niki’s blondie recipe’  It’s actually your recipe :)  

  14. First, I can’t understand why you would have a half a package of oreos left but then I realized not everyone in the world scarfs down any bit of processed sugar as quickly my husband and son do.

    Second, this recipe looks so beautiful and so simple. I need some festive looking bars to include on the Christmas cookie platters I’m giving this year. :)


    1. Ha! Well when you bake as much as I do and have 17 versions of sugar in one cupboard alone, I guess that it’s not as ‘alluring’…haha! Hope you get a chance to try these!

  15. Averie,
    I just posted Mega M&M Blondies.  These are similar but they look easier than mine.  Pinning.
    Have you seen the Mega M&M’s yet?

  16. These bars look amazing, and I love the combo of Oreo’s and M&M’s! These are definitely going on my
    baking list!

  17. Well, it’s too early for me to think about Christmas decorating (although I understand the people who put up their outdoor decorations around here before the snow flies–it makes sense–but do they have to turn on the lights???) but not for Christmas baking! This might be an easy, festive dessert to bring to my extended family’s Christmas celebration (coming up in 3 weeks!). Hmmmm ….

    1. It will be a guaranteed hit if you make it! And in SoCal, with palm trees and 70F weather in Nov and Dec during the daytime, it’s always hard to get in the ‘Christmas mood’, until it hits the 40s at night, then I want to bake and crank my oven!

  18. It’s TOO EARLY for Christmas!!  I mean….I know it isn’t, since OH MY GOD I just looked at the date and we’re only 5 weeks from Christmas?!?!  WTF?!
    I still remember seeing this recipe the first time – so pretty!!  And sccrolling through all the related recipes is just super festive.  Something about m&ms and cookie bars.  LOVE.

    1. I know, I felt like it was a wee bit early to post these BUT we are 5 weeks away and many people do the bulk of their holiday baking right after Thanksgiving and the first week or two in December so I figured okay, why not!

      This recipe and the first time around feels like a lifetime ago :) It was! It’s nice to know you remember it!

  19. These bars are making me drool as we speak! I couldn’t agree with you more, I LOVE the crunchy texture the Oreos and M&M’s give to the soft bars! It’s AHHHHMAZING!

  20. Such winners! I’m a bar fanatic. I think most of my blog recipes are bars because they’re so easy, yet so good! You are the one who taught me to cut them with a sharp chef’s knife for better pics, so I am forever grateful to you for that.
    I want to eat these now!

  21. I love cookies and candy in bars–the more the merrier! I think the mint M&M’s and/ or oreos would be great for the holidays. I’m not ready for winter but I’m always ready for chocolate and mint!

    1. I’m not ready for winter, either! And it finally got ‘cold’ in San Diego the past week and I am not loving it…at all!

  22. Yum! I have a problem with freezing baked goods with M&Ms. I find that after thawing they bleed and look old and unappetizing. Do you have any tips to avoid this?

    1. M&M’s can be tricky with freezing because yes they can bleed and then look a bit ‘old’…sometimes it happens, sometimes it doesn’t, but I can’t pinpoint when/how it will happen so no advice for you there.