Thick and Chewy M&M Cookie Bars

If you’ve been reading for any length of time, you are probably aware of my love for cookies and bars that are thick and chewy. These thick and chewy M&M cookie bars just might be absolute perfection in bar form. :)  They are nice and soft, and of course there are lots of M&M’s sprinkled throughout! I love that half the M&M’s are mixed into the batter, and half are pressed into the top to make sure these bars turn out nice and pretty. I made these for some friends who stayed with us last weekend, and they were gone by the end of the weekend. These M&M cookie bars are definitely a treat you can’t turn down!

Thick and Chewy M&M Cookie Bars

*Note: I baked mine in a 9×9 pan because it was what I had available. However, I do think a 9×13 pan works better.  If you use a 9×13 pan (as written), yours will not be quite as thick.

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Thick and Chewy M&M Cookie Bars

Yield: 1 9x13 pan

Prep Time: 15 min

Cook Time: 30 min

Total Time: 45 min

These cookies are soft, chewy, and chock full of M&M's!


2 1/8 cups flour
1/2 tsp salt
1/2 tsp baking soda
12 Tbsp butter (1 1/2 sticks), melted and cooled slightly
1 cup brown sugar
1/2 cup white sugar
1 large egg
1 large egg yolk
2 tsps vanilla extract
1 12oz bag M&M's, divided


Preheat the oven to 325 degrees. Adjust the oven rack to lower-middle position. Grease a 9x13 pan and set aside.

In a medium sized bowl, whisk together the flour, salt, and baking soda and set aside.

In a large bowl, whisk the melted butter and sugars until combined. Add the egg, egg yolk, and vanilla and mix well. Using a rubber spatula, fold the dry ingredients into the egg mixture until just combined; do not overmix. Fold in 1 cup of M&M's and turn the batter into the prepared pan, smoothing the top with the spatula. Sprinkle remaining M&M's on top and press in slightly.

Bake 25-30 minutes, until the top of the bars is light golden brown, slightly firm to the touch, and edges start pulling away from sides of pan. Cool completely before cutting.

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74 Responses to “Thick and Chewy M&M Cookie Bars”

  1. 1

    sally @ sallys baking addiction — January 16, 2013 @ 8:12 am

    what what what! megan, i posted a m&m cookie recipe yesterday! mine were just peanut butter monster cookies but these bars. oh my heavens. I need these in my life right now. i cannot even believe how SOFT and thick they are. wow, my mind is racing because I want to leave work right now and make a huge batch of these suckers.

  2. 2

    Cookbook Queen — January 16, 2013 @ 9:08 am

    Oh how I need these in my life!!!

  3. 3

    sarah k @ the pajama chef — January 16, 2013 @ 10:34 am

    megan…every single bar cookie of yours i have ever tried has been unbelievable, and i’m sure these are no different! i must make them asap!!

  4. 4

    Linda P — January 16, 2013 @ 11:07 am

    Oh my… I need these now. My mouth is watering!!!! If I didn”t have to work I would be making these now!!!

  5. 5

    Erin @ Dinners, Dishes, and Desserts — January 16, 2013 @ 11:14 am

    Those look amazing! Love all the M&M’s!

  6. 6

    Tasha Zee — January 16, 2013 @ 11:25 am

    They look so rich and chewy …yum!

  7. 7

    Jocelyn (Grandbaby Cakes) — January 16, 2013 @ 11:28 am

    These brownies look so fun! I think they would be fab for the Super Bowl!

  8. 8

    Erika @ The Hopeless Housewife — January 16, 2013 @ 2:51 pm

    These look so good and wouldn’t they be cute for Valentine’s Day with the pink & red M&M’S!

  9. 9

    Cassie | Bake Your Day — January 16, 2013 @ 4:49 pm

    I’m pretty sure I would just eat the whole pan. I love this, Megan!

  10. 10

    Mindy — January 16, 2013 @ 6:07 pm

    These look SOOOOO good! I love anything with M & M’s – they are so colorful and adults and kids seem to enjoy them equally. I like Erika’s idea too!

    P.S. Congrats on your adoption plans – can’t wait to hear more about it!

  11. 11

    Gerry @ Foodness Gracious — January 16, 2013 @ 7:25 pm

    I’ll take a bar over any other dessert any day! These look outstanding Miss :)

  12. 12

    DessertForTwo — January 17, 2013 @ 8:02 am

    Oh, Megan! These look scrumptious! I like to sink my teeth into a thick cookie after a stressful day. Add a glass of wine, and you have dinner 😉

  13. 13

    Jessica@AKitchenAddiction — January 17, 2013 @ 12:20 pm

    I love baked goods that have M&M’s in them! These would disappear in no time at my house!

  14. 14

    Christine (Cook the Story) — January 17, 2013 @ 1:09 pm

    Oh, my son adores M&Ms. I bet he’d love to whip up a batch of these with me. I’m thinking a weekend treat! Thanks for the inspiration!

  15. 15

    Karly — January 17, 2013 @ 3:25 pm

    I love how perfectly chewy these look!
    I might try a browned butter version of these, because I’m sort of addicted to browned butter. :)

  16. 16

    Sara — January 17, 2013 @ 9:35 pm

    I have these in the oven right now for a potluck at work tomorrow! I am so excited! My co-workers were drooling at the pictures!!!! I’ll probably have to sneak one tonight!

    • megan replied: — January 18th, 2013 @ 6:09 am

      I hope you liked them! Let me know how they turned out :)

  17. 17

    Janet — January 18, 2013 @ 11:40 pm

    Made these today…sounded good…no M and M’s on hand so used chocolate and white chocolate chips mixing up was different and they turned out awesome!!! My daughter and husband loved them! Thanks Megan!

    • megan replied: — January 20th, 2013 @ 3:57 pm

      I’m so glad you liked them! They sound great with chocolate and white chocolate chips :)

  18. 18

    Amy S — January 20, 2013 @ 5:53 pm

    I just made these with mint M&Ms and I also added chopped white chocolate and ground flax. Omg so good!! Thanks for the recipe!

    • megan replied: — January 21st, 2013 @ 6:42 am

      Sounds like a great variation – glad you liked them! :)

  19. 19

    Carla @ Carlas Confections — January 24, 2013 @ 5:47 pm

    I absolutely love cookie bars! They are one of my favorite things to make because they are just too easy :) These look so scrumptious!!! 😀

  20. 20

    Tawanda Brown — January 29, 2013 @ 8:07 pm

    I’m trying these for Superbowl!!!

  21. 21

    Ambar — January 30, 2013 @ 3:22 pm

    woohoo! these cookie bars were amazing! I made it last night and brough them to work to give to my coworkers! They all loved them! Great recipe!

    • megan replied: — January 30th, 2013 @ 4:32 pm

      So glad you liked them!! :)

  22. 22

    Amanda — February 4, 2013 @ 9:24 am

    Thank you for posting this recipe! These came out so good. I made them for a Super Bowl party last night and the entire plate went quickly. This was a really great recipe and one I’m going to keep on hand as a party staple. Thanks!

    • megan replied: — February 5th, 2013 @ 6:32 am

      I love comments like these – so glad you liked them!! :)

  23. 23

    Beki — February 8, 2013 @ 2:53 pm

    Hi Megan! I just wanted to say thank you for the wonderful recipe. I made these for a superbowl party, and they were a big hit. I can’t wait to try your chocolate chip cookie dough dip! :)

  24. 24

    weekend highlights | Michael and Tara — February 18, 2013 @ 2:44 pm

    […] and Jeff came over on Sunday night, and we made these M&M cookie bars. Heaven in your mouth, I tell […]

  25. 25

    Tara — February 18, 2013 @ 2:45 pm

    We made these last night and they were DELICIOUS! :) Thanks so much for the recipe! We’ll definitely be having these again.

  26. 26

    Gemma — February 27, 2013 @ 4:20 am

    I am soo excited to make these, i am leaving my current job on Friday so i am making this as a farwell!!! Is the flour self raising???? :) i am trying to translate the ingredients into UK ones as i will be making these at home in not so sunny England!

  27. 27

    Rieneke — March 5, 2013 @ 9:38 am

    These look so yummy I have decided to make them straight away! Will let you know how they turn out. Thx for the recipe

  28. 28

    R — March 6, 2013 @ 10:42 am

    I left them in slighty too long, but they still tasted great. The kids really loved them so this recipe is a keeper!

  29. 29

    Jordan — March 17, 2013 @ 7:41 pm

    I merely stumbled across your post and was compelled to bake these. Let the record state I’ve never baked anything from scratch in my life. Nonetheless, these turned out beautifully, and they taste incredible! If I don’t inhale the entire pan tonight, it will be a miracle. Thank you for sharing your creativity!

  30. 30

    amy @ fearless homemaker — March 21, 2013 @ 6:39 pm

    I made these yesterday and they turned out SO delicious. I’m so thankful I brought most to share with a group, because it would’ve been dangerous to have the whole pan in the house with me. =) I’ll be posting them on my blog either next Thursday or the following Tuesday if you want to check ’em out!

  31. 31

    Sandy — April 9, 2013 @ 4:19 pm

    I just tried these today. They are delicous!! I will be making them again. Thanks for the recipe!

  32. 32

    Jade — April 17, 2013 @ 4:53 pm

    Made these this afternoon. So good. Better than the M&M cookies. Thanks for posting.

  33. 33

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  35. 35

    Elizabeth G. Howard (@smallstate) — May 24, 2013 @ 2:13 pm

    Hi Megan!
    The kids and I just made these yesterday, following the recipe exactly (used a 9X13 glass dish and greased the pan with Crisco). My oven always bakes a little hot so I did them for 24 minutes. They came out PERFECTLY and the kids were crazy about them! I was glad to find this recipe as it is really easy and a good alternative to making cookies, which takes so much longer on the baking side. Thank you! They are ridiculous. Next time I will divide it — half M&Ms and half chocolate chips… I love the chocolate chips better and they kids like the candy as much for the taste as the color! Thank you!

  36. 36

    jan — June 1, 2013 @ 8:41 pm

    Made these today for a graduation party. So easy and very good! WIll definately be making them again.

  37. 37

    Corrie — June 29, 2013 @ 6:12 pm

    made these last night and they where DELISH! only thing that would have made them better was a scoop of vanilla ice cream on top :)

  38. 38

    Jumana Jasir — July 5, 2013 @ 5:52 pm

    Made these today and they are amazing!!

  39. 39

    Sherryl Thomas — July 20, 2013 @ 10:08 pm

    I just made this and i followed the recipe exactly but mine turned into a watery mess. :( I dont know what i did wrong!

    • megan replied: — July 23rd, 2013 @ 12:58 pm

      I’m sorry it didn’t work out for you! Unfortunately, without being there with you, I have no idea what could have gone wrong. Hopefully it turns out better if you try it again! :)

  40. 40

    Emily — July 29, 2013 @ 3:42 pm

    My daughter and I just made these today for soccer practice. They got rave reviews – thanks!

    • megan replied: — July 30th, 2013 @ 8:57 am

      So glad you liked them! :)

  41. 41

    Ellie — July 31, 2013 @ 12:50 pm

    These were so good! I couldn’t wait for them to cool so I committed a sin and ate one….Oh. My. Gosh. Gooey, warm, caramel-y, MnM with a little bit of cookie… almost fudge-y… these are absolutely the BEST cookie bars ever. I like them better than normal cookies. (GASP!!!) God will you forgive me???

  42. 42

    Fiona — October 14, 2013 @ 9:39 am

    Hi. I made these today, I expected them to be almost brownie chewy texture ,like blondies, but mine were sort of a dry cake texture and I followed the recipe to a t. I eve only baked them for 20-25 mins so not to overtake? Should they be more cake or more brownie chewy like?

  43. 43

    May — October 26, 2013 @ 6:32 am

    I made mine exactly as the recipe said but when I took it out the middle was clearly undercooked. I put it back in for 5 minutes and when I checked it again even more of it was the undercooked colour of the mix.

  44. 44

    jennifer dillon — November 28, 2013 @ 3:28 pm

    oooops! we only put 1-1/8 cups of flour…. :\

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  48. 48

    Lisa Chase Patterson — January 19, 2014 @ 11:13 pm

    Made these last night for neice and nephews…all I can say is omg…hot with ice cream, we almost fainted. We can’t stop talking about it. Added about a half cup of heath toffee crumbles to the mix. My daughter who doesn’t east cake or cookies, texted me and asked me to please put another piece up for her before everyone gobbled them down, lol. Thanks, this is now on our ‘list’ (of fav desserts)

    thank you

  49. 49

    Sarah — February 5, 2014 @ 2:15 pm

    I made these yesterday and they were SO good! :o) Thanks for the recipe.

    • megan replied: — February 6th, 2014 @ 10:32 am

      I’m so glad you liked them! :)

  50. 50

    Gemma — February 7, 2014 @ 12:40 pm

    Hey these look amazing! I’m hoping to make on valentines day for me and my bf (but do them in heart shapes!) but I just wanted to check is 12 tablespoons of butter correct? That seems like too much, unless it’s a different measurement in the US? Just wanted to check :)

  51. 51

    Jessica Rose — February 15, 2014 @ 7:24 am

    Just to let you know I have seen this picture uncredited on @theefoodporn twitter and facebook page…they have done this with other bloggers pictures..I have complained….but..

  52. 52

    Lifeisbeauty — March 20, 2014 @ 9:24 am

    OMG these look Devine! I must make these! :)

  53. 53

    Frabrew — March 22, 2014 @ 10:05 pm

    These are literally the best things I have ever eaten in my life. Thank you.

  54. 54

    Gene riddle — April 13, 2014 @ 11:41 pm

    Oh my Goodness! Let me just say Yum! Saw your post for m&m bars and reviews looked promising…. I ran to the store and bought a bag of M&Ms. These were sooo easy to make. Followed prep instructions exactly
    And they were Perfect! Exactly what I was craving. I will make this often. Thank you for sharing. 9×13 glass lined with foil and sprayed worked like a charm too!
    TY TY TY TY TY ❤️

  55. 55

    Jessica B — April 21, 2014 @ 9:49 pm

    These did not disappoint!!! Any idea how to go about adding Peanut Butter to these? Wonder if I could just add it in, or if I would need to decrease some other ingredient….

  56. 56

    Jess — June 15, 2014 @ 1:17 pm

    I’m only 10 and I wanted something simple but yummy to bake, this was perfect! I have now made this 5 times, so amazing!

  57. 57

    Avianti — September 16, 2014 @ 8:26 pm

    These look like the most delicious cookies ever!

  58. 58

    bakeca Avellino — October 8, 2014 @ 4:10 am


  59. 59

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  60. 60

    Sarah Flashing — November 9, 2014 @ 6:06 pm

    I made these for my daughter in law’s birthday today – her name is Megan too, how apropos. :) LOVE how those extra egg whites make the top crackle :)

  61. 61

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  62. 62

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  63. 63

    Ashley — March 27, 2015 @ 3:35 pm

    I made these and they are DELICIOUS! A huge hit at my son’s t-ball meeting. Thank you for the recipe-it’s definitely a keeper!

  64. 64

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  65. 65

    monica — June 2, 2015 @ 1:27 am

    how many does this recipe make?

    • megan replied: — June 9th, 2015 @ 9:33 am

      It makes one 9×13 pan, so it just depends on how small or big you cut them. :)

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