Monster Cookies

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Flourless Monster Cookies made with a few healthier swaps — coconut oil instead of butter and quick oats + peanut butter instead of white flour.

After you’ve gotten hooked on these Flourless Monster Cookies, be sure to try out these other popular cookie recipes: Chewy Chocolate Chip Cookies, Snickerdoodle Cookies, or Oatmeal Cookies.

Image of Flourless Monster Cookies stacked on top of each other with one broken in half showing off the middle/

In case you’re unfamiliar, monster cookies are cookies loaded with peanut butter, oats, chocolate chips, AND M&M’s®. These cookies are meant to be soft-baked and chewy with slightly crisp edges. They’re completely delicious and addictive. Today I’m putting a bit of a healthier spin on these famous cookies. We’re leaving out the flour, reducing the sugar (I know, it’s still a good amount, but most recipes use 1/2 cup or more sugar), and replacing butter with coconut oil.

You can also opt to use dark chocolate which has myriad health benefits. So, let’s get started!

How to make Flourless Monster Cookies

Image of the peanut butter, coconut oil, and sugar in a bowl for these Flourless Monster Cookies.

Step One: Beat peanut butter, sugar, and coconut oil until smooth.

  • We’re using coconut oil in place of butter, which we cream with peanut butter, brown sugar, and solid oil together. If you prefer to use butter you can; use 3 tablespoons.
  • Make sure the mixture is smooth and creamy before adding other ingredients.
  • Add in an egg and egg yolk. You can save the whites and make these Spinach and Feta Wraps after you’re done making these cookies!

Image of the ingredients melted and mixed together for this Flourless Monster Cookie recipe.

Step Two: Add dry ingredients.

  • The great news about these cookies? One bowl. No need to mix dry ingredients separately.
  • Mix in the baking soda (Is your baking soda fresh?), salt, and vanilla
  • Last, but not least, stir in the oats (quick not old-fashioned or steel-cut), chocolate chips, and M&M’s
  • Any flavor chocolate chips work in these cookies. Dark, milk, or semi-sweet chocolate all work in these cookies; it’s up to your preference.


If you have celiac disease, avoiding gluten is an essential health concern. The standard varieties of M&M’s are gluten-free (Milk chocolate, Peanut, Peanut butter, Almond) but some of the special flavor blends aren’t. has an article that lists the flavors that do and do not contain gluten. Most chocolate chips are gluten-free, but butterscotch chips aren’t. Read labels to be sure!

Image of eggs being added to the wet ingredients for this Flourless Monster Cookie recipe.

Step Three: Bake and enjoy!

  • Give the Flourless Monster Cookie dough a quick 10-minute chill in the fridge. Don’t skip this step!
  • Now, roll big balls of dough (3 tablespoons in size) and place them on a silicone liner or parchment paper-lined baking sheet. Aim for only 6-8 cookies per sheet pan because they will spread quite a bit.
  • Bake for 9-12 minutes, watching carefully to avoid overbaking. Ever-so-slightly under-baking these will yield soft, delicious, and ultra-flavorful Flourless Monster Cookies!
  • If desired, add a little sprinkle of salt on top, because… YUM.

Image of the oats, chocolate chips, and M&M's for these Flourless Monster Cookies.

Flourless Monster Cookie tips

  • Use ingredients at the right temperature: When at room temperature, eggs form an emulsion that traps air. While baking in the oven, that trapped air expands and produces fluffy cookies. If possible, use room-temperature eggs for this recipe. Soaking refrigerated eggs in a bowl of warm (not hot) water for about 5-10 minutes is a quick way to get eggs to room temperature.

Image of the baked Flourless Monster Cookies, ready to eat.

More flourless treats

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Flourless Monster Cookies

5 from 4 votes
Flourless Monster Cookies made with a few healthier swaps -- coconut oil instead of butter and oats + peanut butter instead of white flour.
Print Recipe

Flourless Monster Cookies

5 from 4 votes
Flourless Monster Cookies made with a few healthier swaps -- coconut oil instead of butter and oats + peanut butter instead of white flour.
Course Dessert, Snack
Cuisine American
Keyword Flourless Monster Cookies, healthy monster cookies
Prep Time 10 minutes
Cook Time 10 minutes
Chilling Time 10 minutes
Total Time 30 minutes
Servings 13 -15 cookies
Calories 260kcal
Author Chelsea
Cost $4.12


  • 3/4 cup creamy peanut butter
  • 1 cup light brown sugar lightly packed
  • 3 tablespoons coconut oil firm (unmelted)
  • 1 large egg
  • 1 egg yolk
  • 1 teaspoon baking soda
  • 1/8 teaspoon fine sea salt
  • 1 teaspoon pure vanilla extract
  • 1 and 1/4 cups oats quick oats, not instant, steel-cut or old-fashioned
  • 1/2 cup chocolate chips semi-sweet, milk, or dark (use dark chocolate as a healthier substitution)
  • 1/2 cup M&M's
  • Optional: flaky sea salt


  • Preheat the oven to 350 degrees F. Line a large sheet pan with parchment paper or a silicone liner and set aside.
  • In a large bowl, combine the peanut butter, sugar, and coconut oil. Use a hand mixer to beat until smooth. Add the egg, egg yolk, baking soda, salt (omit salt if you plan to add flaky sea salt to the top), and vanilla. Mix well. Stir in the oats, chocolate chips, and M&M's. Beat until combined. Chill the dough for 10 minutes.
  • Roll balls of dough (about 3 tablespoons in size; around 2 ounces in size) and place on the prepared baking sheet. Fit 6 to 8 per cookie sheet--these cookies do spread a bit.
  • Bake 9 to 12 minutes, until they’re just starting to turn golden around the edges. Be careful not to overbake these cookies, as it will take away from the softness of them. Allow to "set" on the baking sheet for 2-3 minutes before transferring to a cooling rack. Repeat until all of the dough has been used.
  • If desired, sprinkle a tiny bit of flaky sea salt on hot cookies.
  • Store completely cooled cookies in an airtight container at room temperature. Cookies are best within 1-2 days, but will last for about 5 days.

Recipe Notes

*Make sure the oats are certified gluten-free if you're gluten-intolerant. Do NOT use instant, old-fashioned or steel-cut oats in this recipe.

Nutrition Facts

Calories: 260kcal | Carbohydrates: 30g | Protein: 6g | Fat: 14g | Saturated Fat: 6g | Cholesterol: 31mg | Sodium: 192mg | Potassium: 153mg | Fiber: 2g | Sugar: 23g | Vitamin A: 59IU | Calcium: 38mg | Iron: 1mg

We do our best to provide accurate nutritional analysis for our recipes. Our nutritional data is calculated using a third-party algorithm and may vary, based on individual cooking styles, measurements, and ingredient sizes. Please use this information for comparison purposes and consult a health professional for nutrition guidance as needed.


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Recipe Rating


  1. Oh my gosh! This is just the kind of recipe I’ve been looking and longing for! You see, I too have gotten in to the habit go peanut butter with a sprinkle of crunchy M&Ms on top 🙂 lol! Anyway, I’ll be trying this sometime this week!

  2. I pretty much eat a spoonful of peanut butter or nutella every day! I just can’t resist it. These cookies look SO good, Chelsea! I love that they’re flourless and on the healthier side. Means I can have two (or five) more! Pinned!

  3. Monster cookies are THE best, hands down. Something about peanut butter, oats, and MnM’s is just plain addictive! Who woulda guessed these were flourless? They’re so fun to look at, I can only imagine how good they taste!

  4. 5 stars
    Look, I’m not an expert cook but I’m trying to be a good cook for my family. And, this go-to snack is perfect for my lovely kids, especially with the M&M’s topping. They love M&M’s. So I’d love to try this one tomorrow to add up to their school snack. But I really wonder, how about using whole wheat flour? You have very good recipes. I will now follow your blog.

    1. I’m sorry, I haven’t tried whole wheat flour in these cookies. If you try the recipe as written, I think you’ll find they don’t need flour as they do really well with peanut butter and oats making up the base 🙂

      1. 5 stars
        Yeah. Peanut butter and oats are good too. I also tried using whole wheat flour as it’s also healthy. Thank you for the prompt response. I highly appreciate it. More power to this blog 🙂

  5. These cookies sound amazing, Chelsea! Love that they are flourless and healthier! My lil guy is a big fan of peanut butter and would totally devour these especially with the pretty pop of color from the M&M’s. They look gorgeous!

  6. I just made these as instructed (minus the m&ms because I never have candy in the house) and they are so good!!!! I had to read the recipe a few times because I kept thinking I messed up somewhere since the dough was crumbly and hard to form into balls, but once I put them together the best I could and into the oven they came out perfect. I will definitely be making these again! The only complaint is that they are so good and made with healthy ingredients that I convince myself that it is okay to have a third and fourth cookie haha, but thank you so much for this recipe!

    1. Haha!! I definitely have the same problem — I always eat way more of a treat when it is healthy 🙂 Thanks so much for your comment; I’m so glad you loved these!

  7. These were so good! To make them vegan, I used a flax egg. I also cut down the fat by replacing half of the peanut butter with powdered peanut butter. Both substitutions worked great! I will definitely be making these again! 🙂

  8. 5 stars
    So delicious! I added shredded coconut and refrigerated the dough overnight and they turned out perfectly.

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