These soft, thick, and chewy monster cookies are about to become your favorite cookie! Loaded with peanut butter, quick oats, chocolate chips and m&m's, these have all that sweet & salty flavor with the perfect chewy texture!
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Why I Love These Monster Cookies
- Thick & chewy: The addition of the quick oats makes these a hearty, thick cookie that you'll love! These are truly the best monster cookie recipe I've made!
- Sweet & salty: Between the peanut butter and candy mix-ins, these monster cookies are the perfect mix of sweet and salty.
- Easy to make! While you do need a mixer to whip these up, these are quick to make in one bowl!
Ingredient Notes
This is just an overview, click here to jump down to the full recipe card for the recipe amounts and condensed recipe instructions.
- Creamy peanut butter: For this recipe, I highly suggest using creamy peanut butter like Jif or Skippy. Natural peanut butter has more oil and will not bake the same.
- Quick oats: These are found in a large cylinder container in the cereal aisle and are different than "rolled oats" in that they're smaller, less chewy, and will bake up quicker. If you only have rolled oats, feel free to substitute for a chewier cookie.
- Unsalted Butter: I personally bake with unsalted butter so that I can control the salt but salted butter will work fine in these cookies; just omit the additional salt!
- Mix-ins: I do a mix of semi-sweet chocolate chips and m&m's but feel free to toss in any candy you'd like!
Make it gluten-free! Use your favorite gluten-free oats and flour to make this gluten-free! My favorite brand is Bob's Red Mill Gluten Free 1-to-1 Baking Flour.
How to Make Monster Cookies:
This is just an overview showing step-by-step photos, click here to jump down to full recipe card with exact instructions.
Step 1: Mix Dough
- In a large bowl, use an electric mixer on medium-high speed to cream softened unsalted butter (½ cup, 1 stick), light brown sugar (½ cup), and granulated sugar (¾ cup) for 1-2 minutes.
- Add in creamy peanut butter (1 cup) and mix until incorporated.
- Add the eggs (2 large) and vanilla extract (2 teaspoons) and mix on low speed until combined.
- Add in baking soda (1 teaspoon) and salt (½ teaspoon) and mix for another 5-10 seconds until combined.
- Add quick oats (1 ½ cups) and all-purpose flour (1 ¼ cups) and mix on medium until combined.
- Add in semi-sweet chocolate chips (1 cup) and m&m's (1 cup) and mix until just combined.
Tip: You may need to stop the mixer & scrape down the sides to incorporate all ingredients.
Step 2: Scoop & Flatten
Scoop dough into ¼ cup (4 tablespoons) sized scoops (I use this stainless steel cookie scoop!), roll into balls, tehn gently flatten each dough ball into a ½" thick disc; this will also help them spread instead of be puffy.
Tip: Press extra m&m's on top of each cookie for a pretty presentation.
Step 3: Bake
Bake at 350°F for 10-12 minutes. Do not overbake. The cookies will continue to bake on the hot pan, allowing them to firm up without overbaking.
Allow to cool, then enjoy! It's important for them to cool; they will be fragile while they're warm.
Frequently Asked Questions
Monster cookies are a combination of peanut butter, oats, chocolate chips, and m&m's! They are the ultimate cookie with the perfect chewy texture and sweet & salty flavor! You can also mix-in white chocolate chips, butterscotch chips, chopped peanuts, and other chopped candy!
Yes you can! Scoop the dough, roll, and slightly flatten then store in an airtight Ziploc bag for up to 3 months. When ready to bake, place on baking sheet and let thaw for 30 minutes or bake from frozen for an extra 2-4 minutes (times may vary with your oven).
The Best Monster Cookies
Ingredients
- ½ cup unsalted butter (1 stick) softened
- ½ cup light brown sugar
- ¾ cup granulated sugar
- 1 cup creamy peanut butter
- 2 large eggs
- 2 teaspoons vanilla extract
- 1 teaspoon baking soda
- ½ teaspoon salt
- 1 ½ cup quick oats
- 1 ¼ cups all-purpose flour
- 1 cup semi-sweet chocolate chips (+ more for topping, if desired)
- 1 cup m&m's + a few extra for pressing on top
Before you begin! If you make this, will you do me a huge favor and leave a review and rating letting me know how you liked this recipe? This helps my small business thrive so I can continue providing free recipes and high-quality content for you.
Instructions
- Preheat oven to 350°F.
- In a large bowl, use an electric mixer on medium-high speed to cream softened unsalted butter (½ cup, 1 stick), light brown sugar (½ cup), and granulated sugar (¾ cup) for 1-2 minutes.
- Add in creamy peanut butter (1 cup) and mix until incorporated.
- Add the eggs (2 large) and vanilla extract (2 teaspoons) and mix on low speed until combined.
- Add in baking soda (1 teaspoon) and salt (½ teaspoon) and mix for another 5-10 seconds until combined.
- Add quick oats (1 ½ cups) and all-purpose flour (1 ¼ cups) and mix on medium until combined.
- Add in chocolate chips (1 cup) and m&m's (1 cup) and mix until just combined.
- Scoop dough into ¼ cup (4 tablespoons) sized scoops (I use this stainless steel cookie scoop!), roll into balls, then gently flatten each dough ball into a ½" thick disc; this will also help them spread instead of be puffy.If desired, press extra m&m's on top of each cookie for a pretty presentation.
- Bake at 350°F for 10-12 minutes. Do not overbake. The cookies will continue to bake on the hot pan, allowing them to firm up without overbaking.
- Allow to cool, then enjoy! It's important for them to cool; they will be fragile while they're warm.
Last Step! Please leave a review and rating letting me know how you liked this recipe! This helps my small business thrive so I can continue providing free recipes and high-quality content for you.
Love this recipe! The cookies are giant and delicious. I baked them to giveaway to the staff at my apartment complex and they were so impressed (& couldn't believe they were homemade). I'm going to keep the ingredients on hand now as one of my go to cookie recipes. Highly recommend!
So awesome to hear everyone loved this recipe so much, Dani! Thank you so much for taking the time to leave a review, I really appreciate it! :)
Excellent cookies! Very easy to follow and turned out perfectly. My first time trying one of your recipes and I’m glad I found it!
I only had traditional Quaker rolled oats, not quick oats, but I briefly pulsed them in a blender and they came out great. I’m not a crazy chocolate person so I used 1/2 the amount of chips and m&ms, but then pressed m&ms in the top. I baked for 12 mins and let them sit on the hot pan and they are perfect! Light crispy edges but soft and cozy.
Huge hit with everyone. Will absolutely make again. Thanks for the recipe!
I'm so glad these turned out with the rolled oats as a substitute! Thank you so much for taking the time to leave a review, Kathleen! I really appreciate it!
These turned out so good. I will definitely make these again! Thank you for sharing this recipe.
So glad to hear you enjoyed this recipe, Kiana! Thank you so much for leaving a review!
Nice soft thick cookie.
This recipe is *chef's kiss* AMAZING. I made several dozen for my husband's work and they got rave reviews. A lot of flavor and texture in just one cookie... but who eats just one?!
Lol, I definitely cannot just stop at one! I'm so glad everyone loved this recipe, Gina! Thank you so much for taking the time to leave a review and trying out this recipe!!
Love that I can make it all in one bowl in under an hour, super quick and an easy clean up! I subbed Reese’s pieces for the m&m’s to make them extra peanut-buttery. I would definitely do as Melissa says and use 1/4 c of the dough for each cookie-it makes wonderful bakery style cookies!
Yumm, I bet the Reese’s pieces substitution was so tasty! So glad you enjoyed this recipe, Kathryn!
These came out perfectly- and so delicious! I was worried they would spread like a lot of cookies tend to do (without refrigerating the dough) but they didn’t! Perfect shape, perfect texture!
Yay, I’m happy you loved these, Erica! I try to avoid a refrigeration step when testing out my recipes (because I’m too impatient for that), so I’m glad these exceeded your expectations! Thank you so much for taking the time to leave a review :)