Monster Cookies! They’re watching youuuu!!! Chewy and tender peanut butter oatmeal cookies, with M&Ms and candy eyes to make Monster Cookies extra spooky for Halloween! They are soft cookies that are really easy to throw together.  

monster cookies recipe

My daughter Valentine is 2, and tosses out random greetings all the time. “Hi mom!” And I always say, “Hi sweetie!” But my phone thinks that I’m saying “Hey Siri.” Every time. 100x a day. And then, after already interrupting my podcast, she waits…”I’m listening.”

monster cookies recipe

Well STOP it Siri. You’re freaking me out. I only want you listening to me when I need to set timers for my kids when they are supposed to be doing something they don’t want to do. “Guys, set the table” (General moaning) “Hey Siri, set a timer for 2 minutes.” That usually does the trick. Thanks Siri. But other than that, go away.

monster cookies recipe

It’s that time of year again. The time when I realize that I’m supposed to have a Halloween costume by tomorrow for the church harvest festival, and we are definitely past the 2-day Amazon Prime shipping mark. I’m not really sure where to go from here. (“To the store,” you say? You mean, leave my house? To buy something? Who has time for that these days??)

Any last minute Halloween costume ideas? Maybe I should just glue some of these M&Ms and candy eyes on my face and go as a monster cookie? Sounds easy, right?

How to make Monster Cookies

mixing mix-ins in dough

gooey cookie dough with mix-ins

This dough, guys.

Siri is always listening…and these monster cookies are always watching. I love monster cookies and this is my new favorite recipe. They are BOMB. I adapted one of my top cookie recipes, Chewy Peanut Butter Oatmeal Cookies, so it’s already off to a great start. All butter dough ( =tons of flavor), tons of peanut butter, and alll the M&Ms.

monster cookies

I wanted these to look like monsters, so I added the eyes, even though I thought they wouldn’t taste great. But I was pleasantly surprised! They are not as hard to bite through as they look, similar in texture to a Smartie, I would say. The kids loved the eyes more than anything.

monster cookies recipe

These are the perfect last minute treat to bring to any Halloween festivities you are heading to this weekend!

If you want to make them REALLY last minute, try skipping the chilling and using the “Spoon Technique” as described in this post for 30 Minute Chewy Chocolate Chip Cookies. I’m obsessed with this! You never have to eat a flat cookie again. Life is good.

how to make monster cookies

Happy Halloween, monsters!

More cookies! Never enough cookies!

Facebook | Pinterest | Instagram


Monster Cookies

5 from 2 votes
Prep: 15 minutes
Cook: 10 minutes
Chill Time: 1 hour
Total: 1 hour 25 minutes
Servings: 30 cookies
Monster Cookies! They're watching youuuu!!! Chewy and tender peanut butter oatmeal cookies, studded with M&Ms and candy eyes to make Monster Cookies extra spooky for Halloween! They are soft cookies that are really easy to throw together.  


  • 1 cup salted butter, softened (2 sticks)
  • 1 cup dark or light brown sugar
  • 3/4 cup white sugar
  • 1 cup peanut butter, creamy or chunky
  • 2 eggs
  • 1 teaspoon vanilla
  • 1 & 1/2 cups flour, spooned and leveled
  • 2 teaspoons baking soda
  • 1 teaspoon salt
  • 1 cup quick oats
  • 1/2 cup old fashioned oats
  • 2 cups M&Ms, plus more for topping*
  • candy eyes, optional


  • In a large bowl or stand mixer, beat the butter for 2 minutes, scraping the sides and bottom.
  • Add the brown sugar, white sugar, and peanut butter. Beat until incorporated.
  • Add 2 eggs and vanilla. Beat well, scraping sides and bottom.
  • Add flour but don't mix it in. Use a small spoon to stir the baking soda and salt into the flour, then beat in gently. There should still be flour streaks.
  • Add the quick oats, old fashioned oats, and M&Ms. Stir until incorporated but do not over mix.
  • Cover the bowl and chill the dough in the fridge for 1-3 hours (or overnight).
  • When the dough is chilled, preheat the oven to 350 degrees F. Line 2 baking sheets with silicone baking mats or parchment paper.
  • Use a large cookie scoop to shape the cookies. (You want cookie dough balls about 2 inches across.) Place on the baking sheet at least 2 inches apart from each other.
  • Bake the cookies at 350 for 10-12 minutes until the centers are alllmost done being shiny. The edges should be firm. Do not over bake.
  • Immediately press more M&Ms and a few candy eyes into the top of each cookie. If you want really tall, chewy cookies, take a spoon and push the edges in toward the middle on each cookies. Check this post for more details.
  • Let cool on the sheet for 5 minutes before removing to a cooling rack. You should definitely eat at least one of these warm. Or maybe 2 or 3. 
  • Store covered on the counter!


This recipe is slightly adapted from my Chewy Peanut Butter Oatmeal Cookies!
*You could also add chocolate chips and/or peanut butter chips. Keep the total level of add-ins to about 2 to 2 and 1/2 cups.


Serving: 1g | Calories: 264kcal | Carbohydrates: 31g | Protein: 4g | Fat: 14g | Saturated Fat: 7g | Polyunsaturated Fat: 2g | Monounsaturated Fat: 4g | Trans Fat: 1g | Cholesterol: 29mg | Sodium: 260mg | Potassium: 93mg | Fiber: 1g | Sugar: 22g | Vitamin A: 236IU | Vitamin C: 1mg | Calcium: 32mg | Iron: 1mg
Course: Dessert
Cuisine: American
Calories: 264
Keyword: Cookies, Halloween, monster
Did you make this? I'd love to see it!Mention @thefoodcharlatan or tag #thefoodcharlatan!

Categorized as , ,

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to and affiliated sites.

You May Also Like...


  1. Yum! Yum! Yum! These cookies look fabulous! I think the monster eyes are adorable! I am going to try these tomorrow. Also, I have never thought of mint chocolate chip cookies! Gotta try those too! Thank you so much for sharing! Can’t wait! As Cookie Monster says….”YUM! COOOK. KIE.”

Leave a Reply

Your email address will not be published. Required fields are marked *

Recipe Rating

This site uses Akismet to reduce spam. Learn how your comment data is processed.