These extra soft and chewy M&M cookie bars are so easy to make—no mixer, no dough chilling, no individual dough rolling required! You can use a mix of regular and mini M&Ms and chocolate chips for texture variety, and change out the colors to make them festive for a holiday.
One reader, Donna, commented: “I made these bars today and I love how quick and easy they are to make. I decided somewhat impulsively to bake and was pleased to find this recipe which calls for melted rather than room temperature butter, and I didn’t need to use the mixer either! These cookies are absolutely delicious and soft and chewy on the inside. ★★★★★“
Finally a cookie recipe without chilling!
Let’s call these no-chill, no-roll M&M cookies! When you need a big batch of cookies but are pressed for time (or mental energy, LOL), cookie bars are the solution. This recipe makes a generously sized 9×13-inch pan of M&M cookie bars, perfect for sharing, especially at the holidays. Kids love these, but so do adults. Seriously, aside from special diets, have you ever met anyone who would turn down a chewy chocolate chip M&M cookie bar? I’m pretty sure I haven’t!
Here’s Why You’ll Love These M&M Cookie Bars
- Like a bigger batch of soft chocolate chip cookie bars—with colorful M&M candies!
- Makes a large pan to serve a crowd.
- A great recipe for young bakers to help with.
- No mixer, no dough chilling, no dough ball rolling—a no fuss dessert recipe!
- Soft in the center, crisp around the edges.
- As easy as a box mix, but way more delicious.
- Add chocolate chips or white chocolate chips for texture variety.
- Choose your color M&Ms to match a holiday or theme.
Unlike these soft-baked M&M cookies, there’s no dough chilling or rolling dough into individual balls and baking in batches. The only waiting you’ll have to suffer through is for the pan to cool for 1 hour before you cut them into bars. (I know, I’m sorry.)
Easy Ingredients, No Mixer
Like with these favorite chewy chocolate chip cookies, using melted butter makes for the softest, chewiest bar cookies. I usually like to use melted butter in bar recipes like brownies and blondies because the bars taste chewy, not cakey. I tested this recipe with creamed softened butter, and the baked result ended up looking more like a puffy sheet cake.
Using melted butter also means you don’t need an electric mixer to make these bar cookies, AND you get that shiny, crackled look on top similar to brownies.
This recipe is similar to the Super Chewy Chocolate Chip Cookie Bars on page 28 of Sally’s Cookie Addiction, but I reduced the sugar a bit, since M&Ms are so sweet. We’re doing away with the extra egg yolk, and instead ensuring softness with an extra 1/2 teaspoon of cornstarch.
It’s also similar to my smaller recipe for chocolate chip cookie bars, but scaled up to make a full 9×13-inch pan. Here’s everything you need:
- Flour: All-purpose flour is the base of this recipe.
- Baking Soda: Baking soda helps these bars rise as they bake.
- Cornstarch: Cornstarch gives the cookie bars that ultra-soft consistency we all know and love.
- Salt: Salt adds flavor and balances the sweetness.
- Butter: Use melted butter in this recipe for the chewiest cookie bars. Because we use melted butter, there’s no need to get out your mixer.
- Sugar: I like to use a mix of brown sugar and white granulated sugar this recipe. More brown sugar than white granulated sugar promises an extra soft and chewy cookie bar because there’s more moisture in brown sugar.
- Eggs: Eggs bind everything together and add richness.
- Vanilla Extract: Pure vanilla extract adds flavor. If you have any homemade vanilla extract, use that!
- M&M Candies: Use regular-size, mini, or a mix of both. I also like to crush up about 1/4 cup of the M&Ms so some are broken, and sprinkle some on top. Totally optional—just adds some texture variety. You can even use different colors for different holidays. I love using red, white, and blue M&Ms for one of my 4th of July desserts.
- Chocolate Chips: I typically use semi-sweet chocolate chips, but feel free to swap them for white chocolate chips, peanut butter chips, or butterscotch chips.
Have I Mentioned No Dough Chilling?
Just melt, mix, press, and bake! Chant it in your head while you get out the ingredients. Melt, mix, press, bake! Melt, mix, press, bake! No dough chill! No dough chill!
The dough will be slick from the melted butter, but should be easy enough to spread/press into the pan. In fact, it doesn’t even look like regular cookie dough and you might remember that from a batch of these chewy chocolate chip cookies. Before & after adding your add-ins:
I strongly recommend lining the baking pan with parchment paper (with overhang on the sides) to make cutting into bars easier. Spread the dough into the pan:
It’s almost gooey-like, so it’s easier to spread than regular, creamy-thick cookie dough. Bake for just 26–30 minutes and avoid over-baking:
I press a few more M&Ms and chocolate chips into the tops of the warm cookie bars, for looks. This is optional. Cool the bars for 1 hour inside the pan, then simply lift the whole thing out using the parchment paper lining. Set it onto a cutting board and slice. They’ll still be a bit warm and that’s fine!
Success Tips for M&M Cookie Bars
- Line the pan so you can easily remove the bars as a whole and slice them, just like I recommend when making rice krispie treats, too.
- Don’t over-bake. Check the bars around 24 minutes into baking, and if you notice they’re browning too much, tent foil over the pan for the remaining bake time.
- Wait at least 1 hour to slice, for neat slices.
Can I Make These With Brown Butter?
Yes! If you want to amp up the depth of flavor by using browned butter, you absolutely can! My team and I have tested it, and you need to start with an extra 3 Tablespoons of butter to make up for the moisture loss that occurs during browning. Otherwise, the bars will taste dry.
Feel Free to Pipe Some Buttercream Decor
These M&M cookie bars are fabulous on their own, but then again, a little frosting is always a good idea. My favorite chocolate buttercream is far from basic; it’s incredibly silky, smooth, and rich. Even though it’s wonderfully creamy, it holds its shape well, and is perfect for piping. It makes a delicious and beautiful finishing touch on this chocolate chip cookie cake, and would have the same effect on these cookie bars if you want to add some flair!
This recipe is part of my annual cookie countdown called Sally’s Cookie Palooza. It’s the biggest, most delicious event of the year! Browse dozens of cookie recipes over on the Sally’s Cookie Palooza page.
Soft M&M Cookie Bars
- Prep Time: 15 minutes
- Cook Time: 27 minutes
- Total Time: 1 hour, 40 minutes (includes slight cooling)
- Yield: 24 bars
- Category: Dessert
- Method: Baking
- Cuisine: American
Description
Think of these bars as no-chilling, no-rolling EASY M&M cookies! Using melted butter, more brown sugar than white sugar, and a touch of cornstarch guarantee the absolute softest, chewiest M&M cookie bar texture.
Ingredients
- 2 and 3/4 cups (343g) all-purpose flour (spooned and leveled)
- 1 and 1/2 teaspoons cornstarch
- 1 teaspoon baking soda
- 1/2 teaspoon salt
- 1 cup (16 Tbsp; 226g) unsalted butter, melted & cooled for just 5 minutes*
- 1 cup (200g) packed light or dark brown sugar
- 1/2 cup (100g) granulated sugar
- 2 large eggs, at room temperature
- 2 teaspoons pure vanilla extract
- 1 and 1/4 cups (about 260g) mini or regular-size M&Ms
- 3/4 cup (135) semi-sweet chocolate chips
Instructions
- Preheat the oven to 350°F (177°C). Adjust oven rack to the center rack position. Line the bottom and sides of a 9×13-inch metal or glass baking pan with parchment paper, leaving an overhang on the sides to easily lift the bars out of the pan. Set aside.
- Whisk the flour, cornstarch, baking soda, and salt together in a large bowl. Set aside.
- In a medium bowl, whisk the melted butter, brown sugar, and granulated sugar together until no brown sugar lumps remain. Whisk in the eggs and vanilla extract. Pour this into the flour mixture and mix together with a large spoon or silicone spatula. The dough will be very soft, slick, and thick. Fold in the M&Ms and chocolate chips. The M&Ms and chips may not stick to the dough because of the melted butter, but do your best to combine them.
- Transfer dough to the prepared baking pan and press/smooth into an even layer. Bake for 26–30 minutes or until lightly browned on the sides and top and a toothpick inserted in the center comes out mostly clean with a few moist (not wet) crumbs. Do not over-bake. If you notice the bars browning too much before 25 minutes, tent the pan with foil. Bars puff up in the oven, but settle as they cool.
- Allow the bars to cool in the pan set on a wire rack for at least an hour. While they’re still warm, I like to press a few more M&Ms and chocolate chips into the tops, just for looks (optional!). Once relatively cool, lift the bars out of the pan using the overhang on the sides and cut into squares.
- Cover leftover bars and store at room temperature for up to 1 week.
Notes
- Make Ahead & Freezing Instructions: You can make the cookie dough and chill it in the refrigerator for up to 3 days or freeze for up to 3 months. Allow to come to room temperature and continue with step 4. Baked and cooled cookie bars freeze well for up to 3 months. Thaw bars overnight in the refrigerator and bring to room temperature before serving.
- Special Tools (affiliate links): 9×13-inch Glass Baking Pan or Metal Baking Pan | Parchment Paper | Glass Mixing Bowls | Whisk | Silicone Spatula | Cooling Rack
- Cornstarch: If you don’t have cornstarch, you can leave it out. The cookie bars will still be soft.
- Butter: Avoid letting the melted butter cool for too long, otherwise your dough will be crumbly instead of soft (and your cookie bars can end up cakey). You want it still warm, but not hot enough to begin cooking the eggs.
- Can I Use Browned Butter? Yes! If you want to amp up the depth of flavor by using browned butter, you absolutely can! My team and I have tested it, and you need to start with an extra 3 Tablespoons of butter to make up for the moisture loss that occurs during browning. Otherwise, the bars will taste dry.
- M&Ms: You can use regular-size, mini, or a mix of both. I like to crush some of them, too, to sprinkle on the top before baking. Totally optional!
- Do I have to add chocolate chips? You can skip the chocolate chips. If you skip them, increase M&Ms to 1 and 1/2 cups (about 300g). You could also replace the chocolate chips with white chocolate chips, butterscotch chips, or peanut butter chips.
- 9-Inch Square Pan: To make a smaller 9-inch pan of cookie bars, use this similar scaled-down recipe for chocolate chip cookie bars. For the add-ins, use 1 cup (200g) of M&Ms and 1/2 cup (90g) chocolate chips.
Reader Comments and Reviews
Wow! Mid way through preparing i realized i didnt have a big enough metal pan, only ceramic. So i used 2 9” metal pie pans, baked for 30 minutes, and cut it like a pie with a little frosting. They are amazing!!
I’m an experienced baker and have made chocolate chip cookie bars literally dozens of times. I followed this recipe to the letter, no substitutions.
This recipe came out greasy, soggy, and seemed raw on the inside, despite a toothpick coming out clean all over, and waiting the hour after baking. The bars peel off of the parchment on the edges and are browned, but they barely hold together. Its like it needs more dry ingredients? Less butter and more egga? I dont know what plagued it, but I will choose a different recipe next time. Very disappointing.
Hi Lala, I’m so sorry to hear this! Happy to help troubleshoot. What kind of pan did you bake them in? And what type of butter? Just wondering if maybe baking in a glass or ceramic baking dish instead of metal could have caused this, or else if you used a particular brand of butter that was higher or lower in butterfat percentage…?
Sounds like Lala problem! I make these every year and they come out perfect!
I made these for Thanksgiving, it’s the first recipe I’ve been disappointed with from Sally’s.
I weigh all of my ingredients so there were no issues with the measurements, but these bars did not have any flavor. The texture was absolutely perfect, but they tasted almost like nothing. I’m not sure what they needed, but this was not a good one sadly.
Love your recipes! Do I need to adjust anything if I use a disposable foil pan? Thx
Hi Chris, you can use a disposable pan for this recipe, no changes needed. Enjoy!
This recipe has always been a hit. But want to try to make individual cookie cakes (4 inch molds). I prefer the taste and texture of this recipe to the original cookie cake. Could it still work or will it set differently?
Hi Sharon, that should work just fine! Bake time will be shorter.
I made these exactly as given using Hershey’s Milk Chocolate bars, a few Almond Joys, and some Peanut Butter Snickers (the latter is a bit weird). Anyway, they came out perfect! I had no trouble with mixing the batter either. They taste a bit like a really good chocolate chip cookie but with candy instead of chips. I will certainly make these again!
To the reviewer who indicated that the bars were “greasy” – I’m wondering if that person didn’t stir the butter with sugars enough? I whisked until I didn’t see any butter – just wondering.
If I only have a half cup of brown sugar could I afford an extra half cup of regular sugar?
Hi Kathleen, that will work in a pinch. The bars may be just slightly less chewy.
Worst ever, which is surprising bc all others have been hits. Tried this bc it was recommended as the double recipe for cc bars that have been perfect. Way too much butter. Oily, greasy, never set up. Will def go back to just doubling the regular cc cookie bar recipe.
Hi, can you add sprinkles to the recipe and, if so, about how much?
Hi Lauren, you definitely can. We’d recommend 1/3 cup, but you can add a little more or less to your liking. Enjoy!
Made it this past weekend on impulse (we had some M&Ms sitting around which doesn’t usually happen) and it was great! The children have loved it, which is what matters most with cookies/cookie-adjacent baking. I must say just glopping the dough into a pan, baking it and cutting it up after it cools feels like a lot less faff than scooping individual balls of cookie dough, so that’s very appealing. Next time I think I’ll make the more basic chocolate chip version, because while I’ve really enjoyed it, the combination of M&Ms *and* chocolate chips would be too much for me on a regular basis. Thanks for another of your reliably excellent recipes.
Has anyone used peanut m&m’s for this? I have a big bag of peanut butter m&m’s and another bag of peanut m&m’s I am trying to find a recipe for! Thanks!
Hi Deborah, you certainly can! You might want to give them a rough chop before adding to the batter.
In the post for your pie crust you say you always use KAF AP flour, but if that is the case your gram measurement for flour is off on this recipe. KAF weighs 120g per cup. Based on this I used 330g of flour for this recipe and it turned out perfect. Can you explain this discrepancy in your recipe?
Hi KK! We measure 1 cup flour as 125g in our recipes. We recommend sticking with the weights listed, but the difference in the final result shouldn’t be huge between the two slightly differing measurements. You can read more about measuring baking ingredients in this post.
These were delicious. The dough was super thick and I wasn’t expecting that. Definitely harder to mix everything in but I managed. This is a recipe that using a mixer isn’t your friend lol. I used a wooden spatula. You certainly can but you’ll have to clean out the dough from the batter a lot to get everything incorporated right. I didn’t use m&ms and just used extra chocolate chips. I’ve made cookie bars before and this by far is the best. Mine were done at 25 minutes. Perfect. I’ll add the m&ms and make them at Christmas this year! They’ll be a hit.
Made as directed and they turned out fine. I am curious if you could use this method of preparing the batter but scoop individual cookies?
Hi Debbie, our M&M cookies recipe is similar!
Hi, I made this recipe a couple years ago for the first time and it turned out amazing. Since then, each time I try to make it I can’t get the right consistency of the dough. It is always really sticky and hard to press into the pan. It comes out cooked uneven and almost like a cake texture. Just wondering if there’s any tips on what I’m doing wrong? I’ve made sure the better is room temp, throughly mixed everything, measured correctly, etc. thank you!
Hi Tori! Avoid letting the melted butter cool for too long, otherwise your dough will be crumbly instead of soft (and your cookie bars can end up cakey). You want it still warm, but not hot enough to begin cooking the eggs. Hope this helps solve your problem!
I tried this recipe for the Fourth of July. As always, they came out perfect. I used my bench knife to cut them up. I will definitely make these for years to come!
They were great! I find dusting the M & M candies and the chocolate chips with 1 tablespoon of the flour helps them adhere to the batter. Much easier to stir in!
My Grandsons birthday is on a Sat. I am having surgery on Thursday; can I make and decorate this cookie bar on Wednesday? I do have a Wilton cake carrier I was going to put it in. Do you think the frosting will hold up and the cookie not harden? Any advice or suggestions would be greatly appreciated.
Wishing you a smooth surgery and a happy birthday celebration for your grandson! You can definitely make and decorate the cookie bars on Wednesday. The frosting will hold up well if the bars are completely cool before frosting and stored covered in your sealed cake carrier at room temperature. Avoid refrigerating, as that can dry out the cookies and firm up the frosting. The carrier is great for keeping everything fresh and secure during transport.
Sooo delicious and easy
Amazing.
The bars were still raw at 30 minutes. Oven differences?
Haven’t baked this yet but I wanted to make this a little thinner than the bars pictured. Would you recommend a 10 X 15 or 11 X 17 sheet pan to make this more like a cookie cake (thinner)? 10 X 15 is about 28% more surface area where as 11 X 17 is about 60% more surface area. Thoughts on which would be better and time to cook? Have you done this before?
Hi Greg, we haven’t tried baking this recipe in pans that size, so are unsure of the exact bake time. We’d probably recommend using the 10×15 pan over the larger one, so you still end up with chewy bars. Hope this helps!
I used a 10 x 15 pan the first time I made these and I just kept an eye on baking time. They were still soft and delish!
Please can you show how you melt butter for use in this recipe as opposed to softened or browning butter? Thank you
Hi Hannah, we melt butter in the microwave in short bursts, stirring in between.
Made these for the first time as a bar & they came out great! Like other reviewers, I was skeptical to determine that they were done but with patience, they surprised me and were perfect. I took them to work and got *a lot* of compliments Be sure to cut them o the small square side as they’re super rich.
Would brown butter work for these?
Hi Carolyn, brown butter would be great in these! You will need to start with some extra butter so you have 1 full cup for these bars. Let us know if you give it a try!
The bars came out very thin and greasy. Also, I had to cook for much longer than the recipe suggests, as they were still raw after 30 minutes. Tastes good, but I won’t be making this again.
The second time I made them, I weighed the flour and sugars on my food scale. I used my measuring cups to see how close they were to the g measurements – and my measuring cups were not even close! The recipe was so much better using the g measure – I think this way I got the proportions better since there was more flour to soak up the butter. It makes sense that the weight is more accurate, but I didn’t know it could be so far off from my measuring cups.
This recipe was very easy to put together but the bars didn’t come out thick & I only got 20 instead of 24. Any idea what could’ve happened?
Hi Regina, the yield will depend on how you cut the bars. They will look a little thicker if cut smaller.
Do you think (or has anyone tried) substituting 1:1 Gluten Free Flour??? Thanks for the reply!
Hi Renee, We haven’t tested this with gluten free flour but let us know if you give it a try.
I do this frequently using King Arthur’s Gluten-Free Measure for Measure Flour. Works fantastic!
Ijust checked my pantry and I dont have any all purpose flour is it alright if I use self rising flour?
Hi Adriana, we don’t recommend self raising flour since they have varying amounts of leavener, so it would take additional recipe testing. It’s best to use all-purpose flour as written.
Delicious, soft. I just baked the cookies right in the small pans, very cute! The buttercream was delicious too and piped great – thank you
Absolutely love this recipe. I use only peanut butter m&ms, no chocolate chips. First time 26 minutes not enough. 2nd time 30 minutes was perfect.