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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!

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.

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!

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!

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






Will rate at a later time. Just wanted you to know that my granddaughter(4) saw these and we shall be making tomorrow. She loves to help me in the kitchen. We are all smiles. 🤗. Thank you!
Love to hear this Jane! Create those priceless memories in the kitchen! Can’t wait to hear how it goes!
We made these today (instead of the next day after I first posted) because we had a slight problem finding the mini M&Ms…..but we finally did! My granddaughter loved helping! I believe she’s going to be a good little cook. These cookies are delicious! She is enjoying them and I know the big kids will too! Thank you! Oh, I bought your cookbook and cried after the first paragraph. So beautifully written. I so look forward to cooking and using this cookbook with my little one! Thank you, again! Jane
Jane!! Thank you so much for the support and encouragement! I’m glad you enjoyed these cookies and even more that you made them with your sweet granddaughter! That’s reason we do what we do! Xoxo!