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.
Craving more? Subscribe to Just a Taste to get new recipes, meal plans and a newsletter delivered straight to your inbox! And stay in touch on Facebook, Twitter, Pinterest and Instagram for all of the latest updates.

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
Did you try this recipe?
Share it with the world! Mention @justataste or tag #justatasterecipes!
This post may contain affiliate links.
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.
Love! My family and co-workers new favorite!
So glad you all enjoyed it, Stephanie!