Preheat your oven for a classic flourless Monster Cookies recipe that’s been in my family for more than two decades.
Chocolatey, chewy, peanut buttery goodness. There’s no better way to describe this tried and tested family recipe for Monster Cookies.
My mom got this recipe from a friend more than 25 years ago, and it’d be impossible to count just how many dozens of Monster Cookies have been baked and enjoyed since that glorious recipe exchange.
These cookies became a staple of mine when I was in college and grad school, and to this day, I’m remembered for their impossibly chewy and soft texture, and of course their unbeatable taste.
My husband jokes that these are a healthy dessert, courtesy of the lack of flour and addition of oats and peanut butter. While “health food” may be a stretch, you can guarantee they are a crowd-friendly dessert. (But if you are looking for a healthy sweet, don’t miss my famous 5-Minute Frozen Yogurt!)
The creepy candy eyes are an optional addition, but they’re a festive decorative touch in October when all things Halloween rule the food scene.
No stand mixer? No problem! I made these cookies dozens of times all through college sans mixer. (Consider the stirring your workout for the day.) And both smooth and chunky peanut butter will work, but I love the added crunch that chunky offers.
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Ingredients
- 1 cup sugar
- 1 cup packed light brown sugar
- 1/2 cup unsalted butter, at room temperature
- 3 large eggs
- 1 1/2 cups peanut butter (smooth or chunky)
- 1 Tablespoon vanilla extract
- 2 teaspoons baking soda
- 1/2 teaspoon salt
- 4 1/2 cups oats (Old Fashioned or Quick)
- 1 cup mini M&Ms
- 1 cup mini-chocolate chips
- Candy eyes (optional)
Instructions
- Pre-heat the oven to 350°F. Line two baking sheet with parchment paper or Silpat baking mats.
- In the bowl of a stand mixer fitted with the paddle attachment, cream together the sugar, brown sugar and butter until light and fluffy.
- Beat in the eggs, one at a time, and then beat in the peanut butter, vanilla, baking soda and salt until well combined.
- Add the the oats and mix until combined, then add the mini M&Ms and mini-chocolate chips.
- Scoop 2-to 3-tablespoon mounds of the dough onto the prepared baking sheets, spacing the mounds at least 2 inches apart.
- Bake the cookies for 12-15 minutes then remove them from the oven and allow them to cool for 5 minutes on the baking sheets before transferring them to a rack to cool completely. (See Kelly's Note.)
Kelly's Note:
- The best way to guarantee your cookies are chewy and not too crispy is to underbake them slightly then remove them from the oven and allow them to cool for 5 to 10 minutes on the baking sheets.
- If you're using the candy eyes, add them to the cookies immediately after you remove them from the oven.
- ★ Did you make this recipe? Don't forget to give it a star rating below!
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Recipe by Kelly Senyei of Just a Taste. Please do not reprint this recipe without my permission. If you'd like to feature this recipe on your site, please rewrite the method of preparation and link to this post as the original source.
Yummy and easy
I have been making these monster cookies same recipie for over 20 years. I always use jif pb creamy. My kids and there friends loved them when they were young. Now my daughter who is now in her 40s makes them for her kids.
Love reading this, Cheryl!
These monster cookies were amazing! Instead of making 2-3 tablespoon balls of dough, I made them 1/3 cup. It made 12 cookies instead of 24 and the bake time was about 20 minutes, I would definitely recommend!
Woohoo! I’m so thrilled you enjoyed the recipe, Ayla!
Best monster cookie recipe in the whole wide world. Sorry not sorry.
I’m so thrilled you enjoyed the recipe! It’s one of my all-time faves, too!
I’ve been making these 4 ever!
Always great cookies!
But this time I made them with Biscoff Cookie Butter and Reese’s Pieces!!
Yup still a breakfast cookie!!
YUM! I’m so glad you’ve been enjoying the recipe, Guin!
I have made these cookies twice now. One of my co-workers said these are the best cookies I have ever made. So from now on these are the only cookies I make. Everybody loves them. Thank you.
LOVE reading this, Laura! I’m thrilled you and your co-workers have been enjoying the cookies!
Delicious!! The only thing I changed was rather than 1 cup M&M’s and 1 cup chocolate chips, I substituted with 1/2 cup each of M&M’s, dark chocolate chips, dried cranberries, and walnuts.
YUM! I’m so thrilled you enjoyed the recipe, Nancy!
Taste=4 stars
Look=2 stars
Instructions=5 stars
These tasted pretty good but it was so so so easy to make. She is amazing at explaining things
I’m glad you enjoyed the recipe, Dominique!
They turn out perfect every time! It’s the best monster cookie recipe I’ve used and the only one I use now!
Woohoo! I’m so thrilled you’ve been enjoying the recipe, Tory!
Nice thing too is that they are not only really yummy, they can be made gluten free (using the GF oatmeal & candies)! Thank you!
YES! You are so welcome, Jane! I’m glad you enjoyed the cookies :)
My husband loves peanut butter cookies so this is now a favorite. I mix up the chips, 1/2 cup mini M&Ms,1/2 peanut butter chips, 1/2 cup semi cho chips, 1/2 cup white chips. Then I add 1/2 cup macadamia nuts. I smash them down & add more of all the chip mix on top..
They turned out Great! Pretty & tastes great!
YUM! I’m so glad you’ve been enjoying the recipe, Christine!
These are the best!
I’m so glad you enjoyed the recipe, Mary Jo!
New family fave!! I use natural peanut butter and add sprinkles for the sprinkle-obsessed kiddos in my family! Huge hit – for both the littles and bigs!
Love, love, LOVE reading this, Cait! My boys are sprinkle-obsessed, too :)
I made a double batch of this recipe. The conversion table erroneously doubles and triples the salt, which completely RUINS the cookies.
if you make a double or triple batch, DO NOT DOUBLE THE SALT!!!
Hi Laurie – I just checked and doubling the recipe will double all ingredients correctly (including the salt). If you’re using kosher salt, doubling should work out great.
These are our favorites!
I’m so happy you’ve been enjoying the recipe, Laury!
How long would you bake in a sheet pan?
Hi Kelly! I have a recipe for Monster Cookie Bars. Here’s the link to the recipe: https://www.justataste.com/monster-cookie-bars-recipe/ :)
One of our family’s very favorite cookie recipes! My kids’ friends love them as well. One friend said she had dreamed about the cookies after she had one that my teen shared with her. :-D
LOVE this! I’m so thrilled your family has been enjoying (and sharing!) the cookies, Jaena.
These cookies are amazing!!! I doubled the recipe and used white chocolate chips and added 2 cups of chopped black walnuts and a cup of raisins….next time I’ll add more raisins. The sky’s the limit on what you can add to these Monster Cookies!!
Yessss! I’m so thrilled you enjoyed the recipe, Julie!
I made these today and they tasted good but where flat and chewy.. could I add an additional minute or 2
Hi Kendra – It’s hard to say what might cause flat cookies. Is your baking soda fresh?
Adding raisins are wonderful just 2 boxes and a Lil less oats. For chewier cookies a Lil less time on the oven
YUM! I’m so glad you enjoyed the recipe, Tamy!
Made these and the Monster bars today and my family was in heaven! Warm bars with vanilla ice cream on top was a hit!
YESSSSS! I’m so thrilled you and your family enjoyed the recipes, Ronnel!
Are you able to prep the dough a day in advance and refrigerate?
Hi Anne! I have never tried refrigerating and then baking the dough, so I cannot say with 100 percent certainty how they will turn out. They will bake up no problem, but it’s more a question of consistency. Let me know if you give it a shot!