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Flourless Monster Cookie Bars

10 Reviews

These flourless monster monster cookie bars may not have flour, but they’re loaded with oatmeal and peanut butter. They’re gluten free and so easy to make!

flourless monster cookie bars

Have you ever had a monster cookie?! They are all of your favorite cookie ingredients combined to make one super epic flavor. Hence, the monster part! And now we’ve got a flourless monster cookie bars recipe for you!

These monster cookie bars are no exception. But the only thing not loaded into these is flour. They’re chewy bars are made with oats and peanut butter only! They stay together with the combination of peanut butter, oats and eggs mostly.

Oh, and NO BUTTER either! The only butter in this recipe is peanut butter.

monster cookie bars

How to make monster cookie bars:

To make monster cookie bars, you’ll start by combining the eggs, peanut butter, sugar and vanilla to a bowl. Use a whisk to combine it all then add the oats and baking soda. Stir in mini M&Ms and chocolate chips then dump it all into 9×9 pan lined with parchment.  Spread it evenly to the corners then you’re ready to bake!

How long to bake monster cookie bars:

Bake these flourless monster cookie bars for 18-22 minutes at 350°F. Start watching the bars at 18 minutes and remove when they start to get brown on the top.

You’ll know they’re done when a toothpick inserted in the center comes out clean!

When you take them out of the oven, allow them to cool all the way in the pan. You can cut them when they’re still a little warm, but you’ll want to wait at least 30 minutes so they set a little more. You can eat them right away or store them for later!

no flour monster cookie bars

How to store flourless monster cookie bars:

Flourless monster cookie bars are best stored in an airtight container at room temperature for 3 days. You can also store them in the fridge for up to one week or in the freezer for up to 3 months!

These flourless monster cookie bars are such a fun recipe to make with kids! I have a feeling your kiddos will think they’re pretty fun to eat too! You could even swap out the regular M&Ms for a seasonal flavor to make them festive, like pumpkin spice or the Easter ones!

monster cookie bar recipe

I hope you love this recipe as much as I do! If you love this recipe give me a virtual high five by following @OhSweetBasil and myself at @What_MollyMade on Instagram! Be sure to tag us so we can see your creations!

More gluten free cookies:

  • Flourless monster cookies
  • Gluten Free Chocolate Marshmallow Cookies
  • Gluten Free Chocolate Chip Peanut Butter Blondies
no flour monster cookie bars

Flourless Monster Cookie Bars

4.5 from 10 votes
Prep Time: 15 minutes
Cook Time: 25 minutes
Total Time: 40 minutes
Servings: 12
These flourless monster monster cookie bars may not have flour, but they’re loaded with oatmeal and peanut butter. They’re gluten free, so chewy and so easy to make!

Ingredients

  • 2 eggs plus 1 egg yolk
  • 1 cup peanut butter creamy, I used JIF
  • 3/4 cup brown sugar light, packed
  • 1/4 cup granulated sugar
  • 2 teaspoons vanilla extract
  • 1 cup oats old fashioned, use gluten-free oats for GF option
  • 1/2 teaspoon baking soda
  • 1/2 teaspoon salt
  • 1/2 cup candy Mini M&Ms
  • 1/2 cup chocolate chips mini semisweet

Instructions

  • Preheat oven to 350°F and line a 9x9 inch baking pan with parchment paper. Set aside. 
  • Using a large mixing bowl, add the eggs, creamy peanut butter, light brown sugar, granulated sugar and vanilla extract. Stir together until combined using a rubber spatula, whisk or wooden spoon.Once combined, add the oats and baking soda and mix well. Then add the M&Ms and chocolate chips and mix well until combined. Dough will be thick and grainy from the sugar.
  • Scoop the dough into the prepared baking sheet and spread the dough evenly to the corners of the pan. Bake in the preheated oven for 18-22 minutes.
  • Start checking at 18 minutes to avoid over-browning. Remove from the oven and allow the cookie bars to cool all the way in the pan before cutting.
  • Sore in an airtight container at room temperature for 3 days, in the refrigerator for up to a week or in the freezer for up to 3 months. 

Notes

These cookie bars can be stored at room temperature for 3-4 days.
Nutrition Facts
Flourless Monster Cookie Bars
Amount Per Serving (1 g)
Calories 314 Calories from Fat 144
% Daily Value*
Fat 16g25%
Saturated Fat 5g31%
Cholesterol 30mg10%
Sodium 267mg12%
Potassium 192mg5%
Carbohydrates 38g13%
Fiber 2g8%
Sugar 30g33%
Protein 8g16%
Vitamin A 76IU2%
Calcium 47mg5%
Iron 1mg6%
* Percent Daily Values are based on a 2000 calorie diet.

A batch of flourless monster cookie bars

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About the authors

carrian feik cheney oh sweet basil

Cade and Carrian have three children and love to spend time together whether it’s vacationing or snuggled up on the couch for a good movie.

And this family especially loves to eat.

They love everything from the keep you fit and healthy to the get out your sweat pants indulgent and everything in between.

But most of all, they love the memories made, shared and treasured and it’s all thanks to a meal shared together with loved ones.

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Recipe Rating




20 comments

  • SO AMAZING!!!

    • Reply
    • Thank you so much!

      • Reply
  • I can’t believe how good these are!! So Delicious I need to hide them or I’ll eat the whole pan myself. I substituted peanut butter chips for the m&ms and just used 2 whole eggs. Perfect!! ❤️❤️

    • Reply
    • Thank you so much Nicole! They are so good they are dangerous!

      • Reply
  • The best easiest gf treat recipe I’ve ever made! Turned out just like the picture. These will be a go to for us!

    • Reply
    • Thank you so much Nancy!! So glad you enjoyed it!

      • Reply
  • I tried this recipe yesterday, followed it to a T and ended up with monster-cookie batter. It never set up, even though it browned and the toothpick came out clean. I’m so confused! I’ll have to try it again and maybe just bake it longer? I baked them for 25 minutes and let them sit until they should have been set. Luckily my guests were good friends and not at all put out

    • Reply
    • I’m so sorry Holly! We’ve made these many times and have never had that problem. Try them again and let us know if they work out!

      • Reply
  • Hi Molly, 
     Thank you for this recipe I can’t wait to try it. I’m thinking of making them as cookies instead of bars?   Hoping it will work ?   I’ve been looking for a recipe like this for a while…a local coffee house makes flourless monster cookies That I just love!!  I’m gluten-free and pretty much sugar free and I’m gonna try my own alternative was sugar by using golden Erythritol  and maybe some coconut sugar ?? I’m Also going to use Lillys sugar free chocolate chips and may or may not put some peanut M&M’s in there??? Hope they turn out!  ❤️

    • Reply
    • Hey Mary Anne! That all sounds delicious! We would love to hear how they turn out!

      • Reply
  • These look great. I wonder if you could sub the peanut butter for almond butter?

    • Reply
    • Hello! We haven’t tried it yet, but our guess is that it would be too watery so you would need to increase the oats a little. If you give it a shot, let us know!

      • Reply
  • YUM!!!! Monster cookies are my absolute favorite cookie; cannot wait to try these! I love how they are made with just oats too 🙂

    • Reply
    • Aren’t they so good?! You’re going to love these!

      • Reply
  • Yay and thank you for a flour- less recipe!

    • Reply
    • You are very welcome!!

      • Reply
  • Can’t wait to start baking!

    • Reply
    • Enjoy!! Thanks for taking time to leave a comment!

      • Reply
  • Hi Molly. First I want to say “Thank you” for sharing these wonderful recipes with us. I do a lot of baking for my mother and I, we are both just big Kids at heart. But must be careful with the sweets we eat. I also bake yummy snacks for my grandchildren.

    • Reply
    • Thank you Mitzi! We hope you and your family love these!

      • Reply

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