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Boooo! Halloween Monster Mash Cookies! Festive, easy, sweet, and gravely spooky! Homemade chocolate chip cookies, made with oats, pretzels pieces, plenty of chocolate chunks, spooky Halloween M&M’s, and crazy candy eyes. There’s nothing not to love about these sweet chocolate cookies with a little salty pretzel crunch. Each bite is slightly crisp on the edges but soft and gooey in the center with melted chocolate throughout.
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Ahhh! I am so happy to share these! In all honesty, I’ve wanted to make these fun, super yummy cookies for months. Actually, since almost a year ago when I made my much loved Christmas Monster Cookies. It was then that I knew that Halloween Monster Cookies needed to follow.
I’m not sure which cookie I love more. Both are unique, special, and melt-in-your-mouth delicious.
I know, I’m such a dork, but nonetheless, I just love how fun Halloween can be!
I wanted to share them very early in the Halloween season. My hope is that you can bake them up for all of your Halloween needs. Parties, school functions, and even just as a fun cookie to bake on a random weekday. Whatever you bake them up for, they require almost no effort!
Spooky details
Start off by gathering all of your ingredients. You’ll need the basics: salted butter, dark and light brown sugar, flour, baking powder, baking soda, and salt – the usuals.
You’ll also need the stir-ins, they’re the most important element of these cookies. You’ll need old-fashioned oats, salted pretzel twists, semi-sweet or dark chocolate chunks, and candy eyes. Plus plenty of spooky Halloween M&M’s, which, of course, make these cookies.
Simply mix up the dough, bake each cookie off, and then enjoy!
We love to eat these cookies warm, just out of the oven. They’re just the right type of gooey delicious cookies to pull out, slightly cool, and indulge in.
One thing that’s important to note, is that these cookies do spread, so don’t stress on that. Because of this, they’re meant to have slightly crisp edges and perfectly soft gooey centers, just like in the photos. My favorite type of cookie. Everyone has really been loving these cookies, they’re definitely an Oslo favorite!
If you want a bit of a thicker cookie, simply omit the additional egg yolk and use only two eggs. As a result, this will give you a thicker cookie without as much spreading.
To get the M&M’s to really pop, I like to add in a few just before the cookies finish baking completely. This way each cookie has a bit of the festive M&M’s right on top.
Excited to see you all bake these up this month! What’s incredible about these cookies is just how easy they are. So have fun with them and enjoy every shamefully sinful spooky monster bite!
Looking for other Halloween cookies? Here are my favorites:
“I put a Spell on You” Poison Apple Martini
Black Widow Peanut Butter Bars
Hocus Pocus Spellbook Brownies
BOO! Chocolate Peanut Butter Bars
Milk Chocolate Stuffed Jack-O’-Lantern Cookies
Lastly, if you make these Halloween Monster Mash Cookies, be sure to leave a comment and/or give this recipe a rating! Above all, I love to hear from you guys and always do my best to respond to each and every comment. And of course, if you do make this recipe, don’t forget to tag me on Instagram! Looking through the photos of recipes you all have made is my favorite!
Halloween Monster Mash Cookies
Ingredients
- 2 sticks (1 cup) salted butter, at room temperature
- 1 cup dark brown sugar
- 1/3 cup light brown sugar , (or more dark brown)
- 2 large eggs, plus 1 egg yolk
- 1 tablespoon vanilla extract
- 2 cups all-purpose flour
- 2 teaspoons baking soda
- 2 teaspoons baking powder
- 1/2 teaspoon kosher salt
- 2 cups old fashioned oats
- 1 1/4 cups Halloween M&M’s
- 1 cup mini pretzel sticks, crushed
- 1 cup semi-sweet chocolate chips or chunks
- candy eyes
Instructions
- 1. Preheat the oven to 350° F. Line a baking sheet with parchment paper.2. In a bowl, beat together the butter, brown sugar, and vanilla until combined. Beat in the eggs and 1 egg yolk, 1 at a time, until combined. Add the flour, baking soda, baking powder, and salt. Beat in the oats.3. Fold in 1 cup of the M&M's, the pretzels, and chocolate chips. 4. Roll the dough into 1/4 cup size balls. Place 3 inches apart on the prepared baking sheet.5. Bake for 8 minutes, then rotate the pan and bake another 2 minutes. Pull the pan out and push the remaining M&M's and candy eyes into the cookies. Bake 2-3 minutes. Remove from the oven and let the cookies cool on the baking sheet. They will continue to cook slightly as they sit on the baking sheet.6. Eat warm or let cool and store in an airtight container for up to 4 days.
Nutrition
Nutritional information is only an estimate. The accuracy of the nutritional information for any recipe on this site is not guaranteed.
Did you make this recipe? Please rate & comment below.
Delicious and I was surprised to find my Harris Teeter had candy eyes!
Hey Lindsey,
Thanks for the thoughtful feedback after trying this recipe, I’m happy to hear it was a win. Have a wonderful day!
Do you refrigerate the dough first thx Debbie
Hi Deborah,
No need to chill the dough for these cookies:) Please let me know if you have any other questions!
These turned out so great!!! I added about 1/4 C peanut butter and used granulated sugar in place of the light brown sugar. So fun and yummy!!! Thanks for sharing another great recipe Tieghan!!
Hey Meghan,
Happy Halloween! 🎃 Thanks a bunch for trying this recipe and your comment! Love to hear it was a winner! XxT
Mine didn’t spread at all, even after I punted the rolling in balls and just flattened them pre-baking (and smacked them on the counter). They were too cakey. Followed the recipe exactly. Are you sure this recipe is correct?
Hi Mel,
So sorry to hear this! Yes, the recipe is correct, I think most people have really enjoyed them:) Was your dough cold? Again, so sorry to hear they didn’t turn out! xx
No I baked them right after making the dough.
My cookies also did not spread. I since learned that adding too many mix ins can contribute to less spread, also chocolate chunks spread more than chips and some flours have higher protein which result in less spread. Next time I will make sure to measure the mix ins more accurately (I think I went overboard!) and use chunks instead of chips. This is a great tasting super fun halloween cookie! Thank you for the recipe!
Thanks so much, Carrie!
Hi Tieghan,
Apologies for asking another question – how many cookie doughs go on the sheet pan at a time? The recipe only stated 1/4 cup and place them 3 inches apart. Can I bake 2 baking sheets at a time if I rotate them half way through?
Many thanks,
Jennie
Hey Jennie,
No worries at all:) I did 5 cookie dough balls on each baking sheet. Yes, you can do 2 at a time, just rotate them! I hope you love these cookies! xT
I made a batch of these for my son who is away at college and my daughters high school field hockey team. A huge hit. So cute and actually very easy to make!
Hey Tamara,
Thank you so much for trying this recipe! Love to hear that it turned out well for you:) Happy Thursday! xT
Can I use quick cooking rolled oats or should I stick with old fashioned oats? Thank you!
Hi Jennie,
I would recommend sticking with the old fashioned oats for this recipe. Please let me know if you have any other questions! xT
This was my 3rd year baking these for my daughter’s teachers! Mine never spread and I follow the recipe to a T – what am I doing wrong?! They still taste delicious!
Hey Lauren,
Thanks for making these cookies each year:) Do you tap them on the counter? That really helps me to achieve a flatter cookie. I hope this helps! xT
Hello, can I make the dough a day ahead? If so, should I let it get to room temp before I bake? Tips suggested
Hey Vanessa,
Totally, that will work for you! Yes, let the dough come back to room temp before baking. I hope you love these cookies! xT
These cookies were absolutely delicious! So soft and gooey. 10/10 would recommend and will be making them for other holidays with diff color m&ms!
Hey Lily,
Wonderful!! So glad to hear you enjoyed these cookies, thanks for making them! xT
Can you explain how to add the mini pretzel sticks? Should they be crushed into a fine powder? Or kept as whole sticks?
Hey Ashley,
You can leave them as whole sticks, they will break down a little once mixed in:) I hope you love these cookies! xT
Can these be frozen and then dethawed later?
Hi Carol,
Totally, that would be just fine for you to do! I hope you love these cookies! xT
This was my first sweet to make from HBH even though I’ve been cooking your meals since 2019! They were great!
Thanks so much, Katrina:) I appreciate you making so many recipes throughout the years! Have the best Sunday! xT
Can’t find those wickedly cool candy eyes anywhere! Where did you find them? I can just find the regular ones – not the ones with eyelashes.
Hey Laura,
I found them on Amazon:) You could also check Target or Walmart. I hope this helps! Let me know if you give this recipe a try! xT
Instead of brown sugar, I used honey. And I used whole wheat flour. I also added coconut flakes, unsweetened, and instead of butter I used coconut oil. And they still turned out. AMAZING!!
Hey Jacqueline,
Wonderful! So glad to hear this recipe turned out for you, thanks for giving it a try! Happy Friday! xT
Hi! I’m wondering if I can omit the oats and if so, would the bake time be different? Thank you!
Hey Brianna,
I have not tested this, but I would add 1/3 cup of flour if you plan to omit the oats. Please let me know if you have any other questions, I hope you love this recipe! xT
Can I add peanut butter to these, will they turn out how much?
Hey Mariah,
Sure, I don’t see why not, I would try 1/4-1/2 cup of peanut butter. I hope you love these cookies! xT
I love baking these cookies! I made them last October and will make them again this afternoon. They both taste and look great! Thank you for sharing your recipe.
Thanks so much, Sandra! So glad you enjoyed these cookies:) Have a great weekend! xT
Great cookies! Make both the Halloween & Christmas versions.
Where can I find the candy eyes with eye lashes?
Note to Canadian followers; the seasonal M&Ms are only available in the States.
Thanks so much Marie!! I found those on Amazon:) Let me know if you have any other questions! xT
Ok, so I made 100 of these bad boys the other night for my kids Halloween class parties and they were a HIT! Did they look exactly like the photos? Of course not! I didn’t expect them too since we all use different brands of ingredients. One thing to note that I think might help some people: If you are doubling the recipe like I did, there is no need to double the eggs! I forgot to do this on accident with my first batch, but they turned out so good I decided to do the same thing with my second batch.
Hey Sarah,
Amazing!! Thanks for the tip on doubling and love to hear that these cookies were such a hit! I appreciate you trying the recipe:) xT