Monster Cookies
Truly the best monster cookie recipe! These peanut butter, oatmeal and chocolate chip cookies are so delicious. They're gluten free, too!
Updated by Kathryne Taylor on September 19, 2024
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“What are monster cookies, though?” I asked recently, with vague recollections of cookies with M&M’s in them.
“Peanut butter, chocolate, and oat cookies.”
“Well, I’m sold.”
This monster cookie recipe took me about eight tries (nine?) to get right, but they are just right.
I almost gave up on them, to tell you the truth. My fella took a batch to work and overheard his coworker say, “This is the best cookie I’ve ever had,” so I knew I was close.
Here they are, in time for a fun weekend baking project or holiday treat. Let’s make some cookies!
These monster cookies are made with more wholesome ingredients than most. They have a classic bakery look and taste, and the sugar content that goes along with that. (If you’re looking for lightened-up, lower-sugar cookies, check these out, or just make half-sized cookies.)
These cookies are essentially made with peanut butter, eggs, coconut sugar or brown sugar, melted coconut oil or butter, and chocolate. They’re flourless and gluten free, as long as your oats are certified gluten free. I like to think that the nut butter and oats make them a little more redeeming.
How to Make Monster Cookies
These cookies are seriously easy to make with basic ingredients. You don’t even need to remember to soften your butter! Here’s the rundown:
- Combine your peanut butter, sugar and melted oil or butter in a large mixing bowl, and mix well. You could do this in a stand mixer, but I hate lugging mine out. I use my beloved hand mixer (affiliate link). You can also mix these cookies with a big spoon by hand, which will take some muscle but it’s totally doable.
- Add eggs, baking soda and vanilla. Mix again. This is so easy, you might as well turn on some music and dance around while you’re working on these.
- Add your oats and chocolate. Mix again. La lalalala.
- Scoop the dough onto a parchment paper-lined baking sheet. These are big cookies that expand while baking, so I can fit six per half-sheet pan.
- Bake for 10 to 12 minutes, until they’re just starting to turn golden on the edges, then let them cool while you put the next batch in the oven. Repeat one more time and you’re done. (If you’re in a hurry, I think you could bake two sets of six cookies at the same time, with racks in the upper and bottom thirds of the oven.)
Monster Cookie Ingredient Considerations
Quick-cooking oats vs. old-fashioned oats
Quick oats disappear more into the cookies, whereas old-fashioned oats offer a more hearty and discernible texture. Did you know that quick-cooking and old-fashioned oats have nearly identical nutrition properties? Quick-cooking oats are just cut up a little more.
Coconut oil (and other oils) vs. butter
I love using unrefined (virgin) coconut oil in this recipe because it lends a very subtle layer of complexity. I can’t really pick out the coconut flavor, but the cookies taste a little more interesting. You could use a mild extra-virgin olive oil (like California Olive Ranch Everyday) or neutral oil, such as sunflower seed oil, but those tend to be more refined.
Butter works great, too, if you’re going for a super classic monster cookie.
Coconut sugar vs. brown sugar
I like to use coconut sugar since it’s a less refined, more natural sweetener made from evaporated coconut nectar. It doesn’t taste like coconut; it’s similar to brown sugar in flavor. It has been gaining popularity over the past few years. I buy it at Trader Joe’s or Whole Foods.
Brown sugar works, too, and costs less. You might be wondering why the recipe calls for 2 1/2 cups coconut sugar or 2 cups brown sugar—they actually are about the same by weight. Coconut sugar just weighs less per cup.
Chocolate chips vs. chocolate-coated candies
Most monster cookies are made with an equal mix of chocolate chips and chocolate-coated candies (think M&M’s). The candies are fun because you can buy colors that match the seasons or holidays (red and pink for Valentine’s Day, pastels for Easter, red and green for Christmas, multi-colored for Halloween, etc.). I bought my naturally colored candies at Whole Foods, near the bulk bins.
However, I also love these cookies with all chocolate chips. I buy bittersweet chocolate chips, so they satisfy my craving for dark chocolate that way.
Watch How to Make Monster Cookies
Change It Up
Mix up your mix-ins.
Like I said, I love these cookies with all chocolate chips (no candy-coated chocolate). You could even substitute some chopped nuts, raisins or other dried fruit for some or all of the chocolate.
Substitute other nut butters.
I can’t get enough of the peanut butter version, but you could substitute almond butter or sunflower seed butter.
Make smaller cookies.
This recipe yields 18 large cookies, which use 1/4 cup dough each. You could easily make 36 smaller cookies by using scoops of 2 tablespoons each. You cookies will bake up faster, somewhere between 6 to 9 minutes. They’re done when they’re just starting to turn golden around the edges.
Please let me know how your cookies turn out in the comments! They’re a real treat and I hope they become your new favorite cookie recipe.
Looking for more chocolate cookies and desserts?
- Amazing (Vegan) Chocolate Chip Cookies
- Coffee Chocolate Chip Blondies
- Mini Peanut Butter Cups and Chocolate Peppermint Cups
- Easy Salted Oat Fudge
Monster Cookies
Truly the best monster cookie recipe! These peanut butter, oatmeal and chocolate chip cookies are perfectly crisp on the outside and tender on the inside. Recipe yields 18 cookies.
Ingredients
- 1 ½ cups creamy or chunky peanut butter (that’s one full 16-ounce jar minus ¼ cup)
- 2 ½ cups packed coconut sugar or 2 cups lightly packed brown sugar
- ⅓ cup melted coconut oil or 5 tablespoons melted butter
- 3 large eggs
- 2 teaspoons baking soda
- 2 teaspoons vanilla extract
- 2 ½ cups quick-cooking oats or old-fashioned oats (certified gluten-free if necessary)
- ¾ cup bittersweet chocolate chips
- ¾ cup candy-coated chocolates (like M&M’s) or additional chocolate chips
- Optional: flaky sea salt, for sprinkling
Instructions
- Preheat the oven to 350 degrees Fahrenheit. Line tw0 large, rimmed baking sheets with parchment paper or silicone mats for easy clean-up.
- In a large mixing bowl, combine the peanut butter with the sugar and coconut oil. Use an electric mixer or a large spoon to mix until well combined. Add the eggs, baking soda and vanilla, and mix well. Add the oats and chocolate chips and mix until they’re evenly incorporated.
- Working with an ice cream scoop or ¼ cup measuring cup, drop the cookies onto the prepared baking sheets. These cookies spread while baking, so leave several inches around each (I can bake six at a time). If they are irregularly shaped at the base, gently shape them into a more rounded mound. If you’d like your cookies to look extra pretty, dot a few extra M&M’s and chocolate chips on each mound of dough before baking.
- Bake 10 to 12 minutes, until they’re just starting to turn golden around the edges. Do not overbake. Let the cookies cool for 10 minutes before transferring to a cooling rack. In the meantime, bake your next six cookies, and so on.
- If desired, sprinkle the cookies lightly with flaky sea salt. Let them cool completely before storing them in an airtight container. Cookies will keep well for several days at room temperature.
Notes
Recipe adapted from Recipe Girl.
Nutrition
The information shown is an estimate provided by an online nutrition calculator. It should not be considered a substitute for a professional nutritionist’s advice. See our full nutrition disclosure here.
My batter was very oily I think from not mixing the natural peanut butter enough. I would use regular peanut butter next time. Flavorful, chewy cookie overall.
Love these cookies! A big hit at our Extended family dinner tonight. I think roasted pecans would be a great addition too.
Aren’t these cookies out of season for Christmas, Easter or Valentine’s Day? The term “monster cookies” makes me think of Halloween.
Hi Bill – as Kate explains above, the term ‘monster cookie’ comes from all the things in the cookie (pb, oats, chocolate chips, m&m’s, whatever else you throw in!). I grew up with these and no one never associated them with a Halloween monster. They can absolutely be made and eaten any time of year.
I made these twice, and the first time I forgot to put the butter/coconut oil in…they actually were waaay better without it! The mixture was a little thick to mix, but they turned out much more delicious in the end!
Dangerously good! My in-laws just texted to say that the batch I sent home with them are the best cookies they’ve ever had. Looks like I’ll be making these for many future family events! I used Little Secrets brand chocolate candies since I don’t eat artificial dyes (i.e. M&Ms brand) and gluten free Bob’s Red Mill quick oats. Turned out perfect. Stick to the baking times, they harden as the cool. Great recipe. Thank you!
They are so good! I’m excited they are such a hit. Thanks for taking the time to review!
These cookies were amazing! My kids decided to make these cookies and they had so much fun with them. I am a cookie snob, but these were excellent cookies in my book.
These make 18 large cookies. How do you store these for a longer period of time? We won’t go through them that quick.
Hi! I’m excited you loved the, Sejal. These cookies freeze great. Enjoy!
Great recipe, thank you! I have made exactly as written-wonderful. Have also improvised with chia egg replacement, once with apple sauce instead of sugar, tried a batch with ‘plant based’ butter alternative- all great! You just know it’s a winning recipe when it can hold up to the challenges of what’s on hand in the pantry and produce something delish every time. My 7 year old daughter is able to help make them and loves eating them- recipe is officially in the rotation!
I love that! Thank you for letting me know this was a hit for your family.
How strange! I replaced with both a flax egg and applesauce and they completely melted. Thankfully it was easy to fix in the second half by stirring in a few tablespoons of flour. Did you use quick cooking oats or old fashioned? I used the latter so I wonder if that’s the difference. If people do want them to be vegan, I would add in up to 8-10 T in the full recipe, personally, or grind up the oats a bit.
These are a winner. In case anyone is curious, they freeze great pre-baked as well. Just scoop them, freeze and bag’em up to enjoy a plateful fresh baked any time you have the craving.
Thank you for sharing your experience, Stakra! I appreciate your review.
What can I use in place of sugar? Would honey or maple syrup work?
Hi Joy, these ones really need the coconut sugar or brown sugar to work.
Can I cut back on the sugar a bit, or is it needed for consistency? It just seems like so much. I don’t need super sweet, just a hint. Thank you
Hi Yvonne, unfortunately you won’t get the same result if you cut back.
These are amazing! After I made them yesterday, I thought I should probably put some in the freezer because I was worried they wouldn’t get eaten fast enough, but never got around to it. My 16-year-old son had 4 of his friends over today and we are currently down to 1 cookie! I think there might be a fight for it Thanks for sharing!
Thank you for sharing, Lissa! I’m excited you loved them.
Love this recipe and I just went to make some and realized I don’t have brown sugar. Can I substitute regular sugar?
Hi Lynda, sorry you won’t get the same result.
SO good!! Perfect for Santa. We let the dough sit in the fridge overnight and baked the next day.
Yes! So good. Thank you for your review, Lindsay.
10/10 will make this recipe again. These are perfect. I do not eat dairy/soy due to an intolerance with my breastfed baby. I subbed the candies for some crushed pretzels and omitted the salt. Also added some soy free sprinkles for the colorful look of monster cookies. I didn’t mean to eat 4 today but — I did.
Do you think this recipe would work as a giant cookie cake?
Hi Al, I’m not sure without trying it. But be sure to report back if you do!
Yum! So decadent.
I’m happy you love them!
These were a favorite recipe, and then we found out one of us has an egg allergy. SO… for those of you trying to make these egg-free, I just had success tonight substituting flax eggs for TWO of the eggs, and a mashed banana for the third egg. This seemed to work better than flax eggs for all three eggs. When I tried ALL flax eggs, the cookies flattened out and lost shape, and they stayed gooey even after lots of extra baking. The banana seemed to add bulk and keep them thicker like the original recipe, and they baked up at about the 20-minute mark using 1/4 cup scoops. I didn’t taste any pronounced banana flavor in the cookies, but I wouldn’t have minded – bananas go great with peanut butter! Also, I opted for butter and coconut sugar — not sure if those options matter to the success we had. I hope these notes help!
That’s hard! But, I’m happy you have found a way you can enjoy them again. I know others will find this helpful, Heather.
Yet another great recipe by Kate! My go-to monster cookies. I find that I can cut the brown sugar to 1 3/4 cup and it still is plenty sweet
Thank you for sharing, Jen! I’m glad they still turn out for your when you adjust the sugar.
Making these right now and they are extremely wet. Having trouble getting them to hold together. I used creamy almond butter, coconut sugar, and coconut oil. Any suggestions?
They smell delish so I’m sure they will taste great.
Hi, Did you mix your almond butter? Maybe try adding a few more oats one table spoon at a time.
These are a family fav!
My daughter is requesting I make a batch to bring to her at family weekend
Do these freeze well? Can batter be made in advance?
These cookies freeze great! Thank you for your review, Julie.
Huge Huge hit all around! I made a few tweaks – due to wanting less sugar and using what I had on hand. Decreased to 1C coconut sugar, added 3T agave; 2T melted coconut oil plus 2T olive oil.
Otherwise, I followed the temp, cooking times and all other ingredients to the tee! These are going to be a standard cookie rotation. **Made a few w/o chocolate chips or M&Ms.
I made these vegan with the flaxseed eggs and vegan chocolates. They were delicious and great for my holiday party! Super straightforward to make.
These cookies taste delicious, but they don’t set up correctly. The tops are golden brown after 10-12 minutes, but the insides are seriously underbaked. Makes them difficult to eat and too gooey. Also, my cookies have a flat, domed top (likely from the 2t baking soda) and don’t look like the photos. Wouldn’t make again :(
Hi ML, I’m sorry you had issues. I tested these a lot and didn’t run into that with the final recipe. How big did you make the cookies? What type of oats did you use?
I had this problem too but I just flattened them out at 10 minutes and cooked for an additional 2-3 minutes and they turned out great.
I looooove these cookies and it’s become our household tradition to make them every Valentine’s Day with some Valentine’s Day m&ms . Thanks for all your tasting Kate because they are perfect!
You’re welcome, Kelsey!
I’ve had multiple people tell my boyfriend he should marry me based on these cookies alone . They’ve become my go-to cookie to bring to events! They’re so easy to make and always a huge hit.
I love that and how funny! Thank you for sharing, Catherine.
I’ve made these before and had good luck, but just made a batch tonight and had the same problem as a previous poster that they were too oily. I think the reason was my natural peanut butter; I used Smucker’s natural peanut butter which is pretty runny. In the past, I think I bought a less oily natural peanut butter and had better results. Next time, I would buy a more traditional peanut butter.
I made these today for a friend’s birthday. They’re delicious! They’re a little sweet though so next time I’ll try reducing the amount of coconut sugar.
I’m happy to hear you enjoyed this, Caitlin! I appreciate your review.
You aren’t joking- these are the BEST cookies! Instant our family favorite. Theyre chewy and crispy. And absolutely delicious. We will be making these many, many times!
Hooray! I’m glad you loved them, Katryna.
These are sooo delicious! They turned out perfect! I was looking for a cookie recipe that my 7 grandkids would like that was healthier and “fun”. I’m bringing them on family vacation.. I’m so sure they will all love them! Thanks for your great recipes!!!
I used a table spoon sized scoop and the cookies still spread and are huge. How can I get them to not spread so much and be a little thicker like your picture? They taste great but they’re so flat!
What type of peanut butter and sugar are you using?
Great tasting cookies but very greasy batter even using Jif peanut butter. I was pleasantly surprised with the texture considering there is no flour in the recipe!
Wow way way too sweet. Even though we all like sweet things this was unpleasantly sweet.
These are the best! Very surprised with some reviews. These are my go to cookie for any gathering. Always a hit!
I use only organic. Never a problem. Always incredible!
I would love these cookies, but I cannot do oats in any form (gf or not) is there anything you might suggest to replace the oats with? Thanks, love following your blog!
I don’t have a good alternative, sorry! I recommend another cookie recipe.
Thanks, Kate, I appreciate your response