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 350ยฐF. 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 Notes
Nutrition
Shoutout
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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.
Amazing! Made them with regular sized m&ms since I didnโt have any minis and they were excellent! Will make sure I have minis on hand to try next time
So glad you enjoyed the recipe, Beth!
These cookies are amazing! I made them for my schools blood drive for the kids who donate and I had none left at the end of the day!
Love reading this, Jayden!
Easy and delicious. Iโve made this recipe several times, itโs always a winner. FYI-I mix creamy and chunky peanut nut butter.
So glad you enjoyed it, Robin!
Great easy cookies! Family loved them and they held up in freezer.
Thrilled you all enjoyed them, Michelle!
I made these cookies for Christmas 2024 and I must say they are the best cookies I’ve ever
eaten!! They are chewy and Delicious!!! I even added a few butterscotch chips and loved it! The options are almost endless. Thanks so much for this recipe!
Love reading this, Donna!
We make these way too much! The best cookies- our famโs favorite. Also a great gluten free option
So glad you’re enjoying the recipe, Ashley!
Me and all my cotmers and family love these
So glad you all enjoyed it, Bella!
Hi, there. Have you ever frozen the dough??? If so, would I bake them straight from the freezer or thaw and then bake?
I had great success making these smaller using the small cookie scoop that’s 1 1/2 tablespoon. In my oven, I baked them for 11 1/2 minutes. YOU ABSOLUTELY MUST LET THESE SIT ON THE BAKING SHEET FOR AT LEAST 30 minutes to set up properly. Longer for the 3 tbsp size cookies.
Excellent recipe that allows you to experiment with add-in’s.
Thank you for sharing.
So glad you enjoyed it, Lisa! Yes, I’ve frozen it before. To bake from the frozen state, you’ll just need to add a few more minutes to the bake time. Enjoy!
I have a recipe very similar to this from who knows when. I can hardly read the recipe card any longer. But this is a smaller batch. I just made my recipe with my grandson to earn a badge. So I’ll have to wait and try your recipe some time later. But thank you for this.
Enjoy, Shar!
How to cook at 325ยฐ instead of 350ยฐ because it was starting to burn the bottom of the cookies
Whenever I make sourdough bread I always put another pan or pizza stone on the bottom rack. It never burns the bottom of the bread anymore. Maybe it will work the same for cookies
Great idea, Susan!
My favorite monster cookie recipe! I get compliments whenever I bring them anywhere!
So glad you’re enjoying them, Alicia!
Best cookie recipe ever! Iโve never really liked baking cookies but this one is so easy and everyone loves them! My granddaughter gives them a solid 7.5-8. I give them a 10+.
Love that you’re both enjoying the recipe!
I make these cookies also, definitely one of my favorites. In mine though I also add a cup of raisins, then along with the eyes, I also give them gummy worm smiles. I would send a picture but I don’t see any place to do that.
Thanks
Steven.
Just got your picture via email, Steven! Love it!
These are so delicious. I will definitely be making them again.
Thrilled you’re enjoying it, Debbie!
Love this recipe. Made it all the time, then wife went vegan; now i make them vegan (use 1:3 tbsp flax seed to water and dark chocolate instead of milk). Good recipe, can do a lot of variations.
So glad you enjoyed it, Andrew!
I have a recipe from the 80โs but it makes a huge batch. This is the first smaller batch recipe that turns out like my recipe! These are great! Thank you!
So glad you enjoyed the recipe, Kathy!
Made these last night and they are so good, crispy edges but a soft and chewy center I will be making these again. Thank you for this yummy recipe!
So glad you enjoyed it, Alyssa!
I add one ingredient to this recipe and it has become everyone’s favorite
So glad you are enjoying the recipe, Jarines!
Made and sent to my new son-in-law who is Air Force and training in special forces. They traveled well but I did individually wrap since it is going into heat! He loves them and they are a special homemade treat that satisfies!
Love reading this, Brenda! So glad your son-in-law enjoyed them!
YUM!!! Always popular.
So glad you enjoyed it, Sandra!
Love this recipe!
Thrilled you’re enjoying it, Kathy!
These are by far the most favourite cookies. My children & grandchildren agree
So glad you enjoyed the recipe, Lori!
Delicious and easy to make!
So glad you enjoyed it!