Chocolate Chip M&M Cookie Bars are something that I make almost weekly! Here’s why:
- The butter doesn’t need to be softened.
- The dough doesn’t need to chill.
- You make it all in one bowl with a spoon and not a mixer.
- Because they are cookie bars they are even faster to make than cookies. Spread in a pan and bake.
- They taste so good!!!
So basically I used my favorite easy chocolate chip cookie recipe, added M&Ms and baked in a 9×13 inch pan for 20-25 minutes at 325. If I need to make a double batch I will double the recipe and spread it in a cookie sheet pan (11 inches by 17 inches) and bake for 20-25 minutes at 325.Print
Chocolate Chip M&M Cookie Bars
- Prep Time: 15 minutes
- Cook Time: 20 minutes
- Total Time: 35 minutes
- Yield: 1 (9x13 inch) pan 1x
These are my favorite chocolate chip cookie bars to make. The work to taste ratio is absolutely perfect. NO CHILLING is necessary and you don’t even use a mixer. I’ve made these probably 50 times and they never get old, especially with the addition of M&Ms.
- 3/4 cup (1.5 sticks) of unsalted butter (no substitutions)
- 3/4 cup (150 grams) brown sugar
- 1/2 cup (100 grams) white sugar
- 1 egg
- 1 egg yolk
- 2 tsp vanilla extract
- 2 1/4 cup (280 grams) all purpose white flour
- 1 tsp baking soda
- 3/4 tsp salt
- 1 1/2 tsp cornstarch
- 1 cup semi-sweet chocolate chips
- 1 cup M&Ms
- Preheat your oven to 325°F. Add the butter to a medium sized microwave safe bowl. If the butter is straight from the refrigerator put it in the microwave for 45 seconds. It should be half melted and half super soft. If the butter was from the freezer it will take a bit longer.
- Add in the brown and white sugar. If you have a kitchen scale *(this is the one *I use and is super cheap) use that instead of measuring cups. It is more precise and will lead to a better cookie.
- Stir the butter and sugar together until smooth with a whisk.
- Add in the egg. Whisk until smooth.
- Add in the egg yolk. Whisk until smooth. (if you don’t know how to separate an egg here is a good tutorial).
- Whisk in the vanilla.
- Add the flour on top of the wet ingredients (use a kitchen scale if possible). Don’t stir just yet. Now add in the baking soda, salt and cornstarch. Now stir with a spoon,folding the flour into the wet mixture rather than mixing or stirring vigorously.
- Now add in the chocolate chips and M&Ms and fold in until combined.
- Spray a 9×13 inch pan with non stick cooking spray.
- Use a spatula to spread and dough into the pan evenly.
- Bake on the middle rack for 20-25 minutes, or until a toothpick inserted in the middle comes out clean. Let the pan sit on a cooling rack for 10 or more minutes. Slice into squares and enjoy! Store leftovers in an airtight container in the freezer.
Make sure to use a good brand of chocolate chips. I really like Guittard, Ghiradelli or Hershey’s Special Dark*.
I like to double this recipe and bake it on a cookie sheet (11 inches by 17 inches).
- Category: Dessert
Allison Cassel says
I tried these out tonight, using 1 2/3 cups of chocolate chips, and 1/3 cup “Yummalo” baking mix (it’s a mix of sprinkles, tiny marshmallows, and tiny vanilla chips, all in bright colors); they turned out fantastic and got great reviews! I love the idea of making chocolate chip cookies, but not so much the actual process; this was much easier and I’ll be using it again for sure, especially since chocolate chips are probably going to be on sale for the holiday baking season soon, and it’ll be fun to mix up some of the other flavors out there.
Love those ideas!
Jeff Winett says
This was definitely a first for me. I’ve never made a Karen Peterson recipe that wasn’t from an Instant Pot, until yesterday. If your M & M bars are an indicator of other tasties up your sleeve that bake in a regular oven, please keep them coming! These were easy, and ridiculously sensational. I’ve tried M & M “cookies” before, and always felt they were good, but not much more than that. These Bar cookies were way different. Chewy with a little crispy around the edges….but what was also super enjoyable, is that while eating, every once in a while you will get a little crunch from the shell of the M & M’s. I am hooked, and because they are so easy to get into the pan, this could become dangerous 🙂 Big Sherman Oaks, California thanks Karen, for what you’ve shared.
I’m so glad you branched out and tried this! I do agree with you the crisp of the M&Ms makes a perfect bite
Hi Karen, Allie here. The above recipe would be great if such a thing as S.F M&M’s for us diabetics, but alas…..
Sorry Allie! This is definitely not a good recipe for a diabetic 🙂
Hello Karen. Just wondering why the no salt butter. If I used regular salted buttter, would I then just eliminate the added salt for this recipe? Can’t wait to try this.
I use unsalted butter to control how much salt goes into my recipes. if you use salted butter I would use somewhere between 1/2 tsp and 3/4 tsp of salt. I would say 2/3 tsp but I don’t think that’s actually a measurement on any measuring spoons I’ve ever seen 😉
Good morning!! I was wondering it says to store the leftovers in the freezer,so my question is: do the leftovers have to be stored in the freezer or can they be stored in an airtight container on the counter?
Yes you can store them on the counter. They’ll be good for about 3 days.
J JO says
Karen, I gained 300 calories just looking at your full pan photo! Ohh, that looks sooo good! YIKES!
So…we’re having Instant Pot lettuce tomorrow, I heard you say? : )
Super easy and very yummy! This will be my go to cookie!
I doubled the recipe. Used 1-1/2 cup M&Ms, 1-1/2 cup Ghiradelli semi-sweet chocolate chips, and 1 cup Ghiradelli white chocolate chips. Received rave reviews! This will be my quick go to dessert to bring! So easy and yummy!
Yum that sounds so tasty!!
So I doubled the recipe and the cook time that was needed was way longer than 25 mins I baked the sheet at 325 for almost 45 mins and the mix is still not done in the middle. What did I do wrong? The top layer is done perfect golden brown color. 😩 this may not turned out as planned.
How did it go? I bet it was still good? Sometimes different pans and different ovens cook differently.
Nancy Baxter says
Never see this recommended, when I double a recipe I always calculate square inches in recommended size baking sheet then calculate square inches in a larger sheet pan, this is a guide, baking time may need to be adjusted a bit–
How long do you suggest baking these if I’m going to use an 11 x 17” sheet pan?
Are you doubling the recipe? If so then keep the same cooking time. If you’re not doubling it the bars will be a lot thinner and will cook quickly. So I would suggest a 15 minute baking time. But watch them close, since this is just a guess. I haven’t tried it myself.
Stew Thiel says
Thank you Ms. Karen! Made this afternoon with my 3 and 6 year old daughters. They absolutely LOVED them!!! My 6 year year old first grader said “OMG, these are so good daddy”! My 3 year old repeated her sisters sentiment!!!
Doubled the recipe in a Calphalon Non Stick Classic Jelly Roll Pan Dimensions 1.08 inches (H) x 12.8 inches (W) x 17.76 inches (D)
Actually just says 12 x 17 on the pan, but it worked great and now we have WAY too many leftovers!!! I’ll probably buy the smaller pan the next go time. I usually prefer using Karen’s recipes to the T, but my 3 year old asked me if we could use Reese’s pieces instead of M & M’s. OMG Karen these cookie bars are so good! Thanks for another great recipe!
So glad you enjoyed them!!
Hello! This recipe looks delicious! Do you think I could add a box of vanilla pudding to the mix, just like some cookie recipes call for??
probably you could! I am not sure what exactly would happen and what it would taste like, but you could try it.
What do you think the effect will be if instead of using the 1 egg yolk, I actually used the whole egg? I don’t cook or bake often so I don’t want to keep 1 egg white around. Do you think it will make a big difference?
I love your recipes!
I bet it would be just fine.
Just made this yesterday with 2 eggs instead of 1 egg & 1 yolk and it was delicious! It’s a nice cookie bar that’s a bit more “fluffy” than store bought cookie bars when made this way. So yummy! Now I need to buy an 11″x17″ cookie sheet so I can double the recipe! 😀
doubling is a happy life!
FYI….when you said you doubled the recipe and put it in a jelly roll pan? Yea, that’s not the size pan that is needed. A jelly roll pan is 10 1/2 by 15 1/2 inches, and I used that based on your recipe. I now have a mess to clean in my oven because the batter overflowed! I used my kitchen scale to measure all the ingredients. Now that I’ve actually baked it, I suspect you actually wanted the baker to use a 12 by 17 pan. Please actually MEASURE your pan sizes before you make a recommendation and make your recommendation based on size only….it will save others from having to clean their oven….
Julia, I’m very sorry that this happened to you. I will correct the information so no one else has this problem.
Delicious! I made these this afternoon with my (almost) three year old daughter and they were a hit. I loved that it’s a quick and easy recipe, which is a must when baking with a toddler! They turned out great and will become a go to for a quick treat in our house. I can’t wait to try switching up the M&Ms and chocolate chips for other yummy add ins too, not that the original isn’t fabulous, it’s just what I do 😉
So glad you tried them Elissa! I bet butterscotch chips would be good as well as lots of other things!
Cecilia Orozco says
What does the cornstarch do?
these cookies are thick and puffy. It’s the cornstarch that gives these cookies a lift.