M&M Cookie Bars!! One of my favorite desserts of all times. And also be warned - one is NOT to be left alone with a pan of these! These cookie bars are on par with my famous cheesecake cookie bars. You may want to check those out as well!
Table of Contents
Why I Love This Recipe
Is there anything better than a soft cookie in bar form? Where the edges are just lightly golden brown and a tad bit crunchy... and the inside is gooey and soft and melts in your mouth? Let me answer that for you.... no.
It doesn't get better than cookie bars when it comes to a quick and easy dessert that literally every single person will love. These cookie bars are my favorite sugar cookie recipe baked up in bar form. You all know how I love the giant M&M cookies and these are just the perfect bar form for that perfect cookie!
Ingredients & Substitutions
- Butter
- Light Brown Sugar
- Vanilla Extract
- Large Eggs
- All Purpose Flour
- Baking Powder
- Baking Soda
- Christmas M&M’s
- Maldon
*For a full list of ingredients and instructions please see recipe card below.
How to Make M&M Cookie Bars
Step 1: Preheat the oven to 350 degrees. In a large bowl, combine the melted butter and brown sugar and mix with a wooden spoon for 1 minute until combined.
Step 2: Add the vanilla and eggs, making sure to scrape down the sides of the bowl, and mix until fully incorporated.
Step 3: Add the dry ingredients into the bowl and slowly mix until just combined. The batter will be a bit stiff, but that's normal.
Step 4: Fold in 1 cup of the Milk Chocolate M&M’s.
Step 5: Spray a 9x9 metal baking pan (see note above) with baking spray and line it with parchment paper. Spoon the batter into the prepared baking sheet and sprinkle with the remaining Milk Chocolate M&M’s and Maldon sea salt if desired.
Step 6: Transfer it into the oven. Bake for 35-40 minutes. Once the bars have baked, remove them from the oven and let cool for at least 2 hours before cutting and serving.
How to Store M&M Cookie Bars
Cut these into squares once cooled, and store in an airtight container for a few days. You can also store in the fridge to keep them longer, about two weeks.
How to Freeze M&M Cookie Bars
We have not had leftovers for these in our household! However, if you want to freeze them, store these bars in a freezer bag or airtight container for about 3 months. Defrost in the fridge or outside to serve.
Tips & Tricks
1: Use a 9x9 pan. Don't try and do it in a 9x13 or an 8x8... it won't be the same. Trust me - there's a reason I developed it this way! And a glass or ceramic baking dish doesn't retain heat the same way a metal baking dish does... so use a metal baking dish! And 8x8 (while it's the same shape is only 64 square inches and a 9x9 is 81 inches. So that will WILDLY affect baking time.
2: Don't skimp on the M&M's and the sprinkle of salt on top. It really makes all the flavors sing! If you want to add more M&M's mid bake, that will ensure they don't fall to the bottom of the pan.
3: After the baking time - LET THESE SET FOR 2 HOURS. These cookie bars might look a little under-baked but they need time to finish residual baking once they come out of the oven.
4: Proceed with caution once these cookie bars are baked and cut. I've eaten pretty much an entire pan once before and I'm not even remotely exaggerating. Thomas had to remove the last 2 squares from the house because I could NOT BE STOPPED.
FAQs
What is the difference between cookies and cookie bars?
Cookie bars are somewhere cakes and cookies. A great and easy way to make a big batch, and the thickness gives them a nice gooeyness. While not all cookie recipes may be suitable for cookie bars, this is a great one! Thickness is also important when baking bars, too thin and it will be too crisp, too thick and the edges will be brittle by the time the center bakes.
Can I add other things to these cookie bars?
Yes! Add nuts, pretzel, chocolate chips- all perfect additions to these bars.
Similar Recipes
If you tried this recipe, please leave a 🌟 star rating and let me know how it goes in the 📝 comments below. Thanks for visiting today
Soft Sugar M&M Cookie Bars
Ingredients
- 1 cup butter melted
- 2 cup light brown sugar
- 4 teaspoons vanilla extract
- 2 large eggs
- 2 cups all purpose flour
- 1 teaspoon baking powder
- ¼ teaspoon of baking soda
- 1 cup Milk Chocolate M&M’s plus extra for garnish
- Maldon sea salt optional
Instructions
- Preheat oven to 350 degrees.
- In a large bowl, combine the melted butter and brown sugar and mix with a wooden spoon for 1 minute until combined. Add the vanilla and eggs, making sure to scrape down the sides of the bowl, and mix until fully incorporated.
- Add the dry ingredients into the bowl and slowly mix until just combined. The batter will be a bit stiff, but that's normal. Fold in 1 cup of the Milk Chocolate M&M’s.
- Spray a 9x9 metal baking pan (see note above) with baking spray and line it with parchment paper. Spoon the batter into the prepared baking sheet and sprinkle with the remaining Milk Chocolate M&M’s and Maldon sea salt if desired and transfer it into the oven. Bake for 35-40 minutes. Once the bars have baked, remove them from the oven and let cool for at least 2 hours before cutting and serving.
Notes
- Use a 9×9 pan. Don’t try and do it in a 9×13 or an 8×8… it won’t be the same. Trust me – there’s a reason I developed it this way! And a glass baking dish doesn’t retain heat the same way a metal baking dish does… so use a metal baking dish!
- Don’t skimp on the M&M’s and the sprinkle of salt on top. It really makes all the flavors sing! If you want to add more M&M’s mid bake, that will ensure they don’t fall to the bottom of the pan.
- After the baking time – LET THESE SET FOR 2 HOURS. They might look a little under-baked but they need time to finish residual baking once they come out of the oven.
Nutrition Information
Photography by Matt Armendariz / Food Styling by Adam Pearson
If I double the recipe do you think you could use a 9X13 metal pan?
1 1/2 the recipe would work for a 9x13!
I am a semisweet purist but these were DELICIOUS. One thing- I bought the 9x9 metal pan per Gaby's instructions and the bars were definitely baked in 25 minutes, not the 35-45 min recommended. Usually my oven is pretty typical but I'm glad I checked these well before my timer went off. Needless to say, I had thirds.
I have made them twice. Both time with 8x8 metal pan. Each time cooked for 45-50 minutes and the middle was gooey. What am I doing wrong?
the different between a 9x9 and an 8x8 is actually quite a big difference and it might take even more time. Do you have anything that's a little bit wider so it's not as thick
hi! could you add more ingredients - like crushed pretzels, marshmallows & m&ms?
sure - but not too much bc you dont want to overcrowd
I only have a glass pan. What changes should I make to the recipe??
your baking time will need to be adjusted as glass doesnt retain heat as well - keep your eyes on it as it will need a bit longer
Love these bars! Question each time I make these the outside gets crispy and the middle sinks while cooking. Any ideas? I use a 9x9 metal pan.
These look great. Would I be able to use peanut butter M&M's instead of regular?
sure thing
Gaby! So delicious! I have a 3- and 5-yr old, and we all made these together. Huge hit from start to finish, and super fun with the Valentines M&M colors!
Unsalted or salted butter?? Gonna try whipping these up when the kiddos take a nap (ha... yeah right they'll nap!).
unsalted
If I only have an 8 x 8 can I still do these? Any modifications?
yes - might just take a few extra minutes to cook through
Gaby, what kind of baking dish do you recommend? Metal vs. glass? I made the snickerdoodle blondie bars in my glass dish and they were gooey in the middle so I am guessing I should make these in my metal pan? Also could this recipe be doubled and cooked in a bigger dish (9x13)?
9X9 always metal. Glass doesnt retain heat very well
If I am going to freeze these should I freeze the whole thing or cut them first?
I would cut - that way you can take them out 1 by 1 and eat them as needed!
unless you're planning to serve the whole thing... then freeze whole
Made these today and only had an 8x8…so I ate a few scoops of batter and hope it makes up for not having the bigger pan
In this recipe, is the brown sugar supposed to be packed? I made these and packed it (thinking cookie recipes usually say to do that) and they turned out yummy, but so sooo sweet lol. Almost like caramel. And all the m&m's sunk to the bottom except the ones I put on top before baking.
My sweet tooth is pretty intense but how sweet these turned out is a lot even for me lol. I have to imagine I wasn't supposed to pack the sugar though, right? If you were able to add gram measurements on baking recipes that would be hugely helpful!
I pack it!! They are def sweet 🙂
Followed the recipe, cooked for 35 mins and was completely over baked, not moist at all 🙁 but still tasty!
Should I reduce the time next time? I used a glass tray as I don't have a metal one, but that can't be the reason to overbake I assume?
Also would really appreciate gram conversion in the recipes.
Thanks !
did you follow the recipe as printed? or was there any type of conversion that you did? any ingredient substitutions?