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Monster Cookie Bars

This Monster Cookie Bars recipe is filled with M&Ms, chocolate chips, peanut butter, and oats. Since these monster cookies are flourless, they are a gluten-free bars recipe. 

No Flour Monster Cookie Bars Recipe

Calling all cookie lovers! If you’re looking for an indulgent treat that’s sure to impress, check out our Monster Cookie Bars Recipe. This delicious batch of cookies is a real crowd-pleaser – we’ve taken it to work, and given it to friends, and each time, it gets rave reviews. So don’t miss out on making these mouth-watering flourless monster cookies.

Flourless Monster Cookie Bars Recipe

These decadent Monster Cookie Bars contain no flour, yet pack all the deliciousness that cookie lovers crave! Our gluten-free recipe uses oats, peanut butter, butter, sugar, and eggs to create an indulgent cookie bar that’s sure to satisfy.

So, if you’re looking for a special treat or just trying to cut back on flour this Monster Cookie Bar is the perfect solution!

No Flour Monster Cookie Bars Recipe


  • A fun twist for these m and m cookies is to swap out the baking M&Ms with regular-sized seasonal colored M&Ms. For example use Christmas, Valentine’s, and Easter theme colored M&Ms.
  • Swap out M&Ms for Reece’s Pieces for Fall color! These are gluten-free also.
  • Use team colors to show some spirit!

If you are on a strict gluten-free diet double check as some M&Ms Candies (pretzel & crispy) contain gluten.

It’s totally fine to use regular-size M&Ms when the store is out of baking mini M&Ms – and that’s exactly what we did when we were craving delicious cookies! Nothing was going to stand in our way – not even the size of the M&Ms.

No Flour Monster Cookie Bars

Ingredients for Monster Cookie Bars

Take a bite into these delicious, soft and chewy peanut butter oatmeal cookie bars! Bursting with luscious chocolate chips and colorful M&M’s – these confections are the perfect indulgence for cookie lovers. All the best ingredients, all in one decadent dessert. Go ahead and treat yourself and gather your ingredients.

  • Brown Sugar
  • White Sugar
  • Salted Butter
  • Creamy Peanut Butter
  • Eggs
  • Vanilla Extract
  • Quick Oats – We use both Quick and Old Fashioned oats for texture.
  • Old Fashioned Oats
  • Mini M&Ms
  • Mini Chocolate Chips – All Nestle Chocolate Chips are gluten-free except for the butterscotch chips.

Baking M&Ms are found in the baking section of your grocery store. Not in the candy aisle. The “baking M&Ms” is cheaper than the M&M minis in the candy aisle for us! If you can’t find mini M&Ms in either aisle of your local store you can order them on here. 

No Flour Monster Cookie Bars Recipe


Another thing we use when making these is a baking mat. If you don’t have a baking mat you can use parchment paper. The baking mat is reusable and easier to work with. Here are the baking mats we use but any brand of baking mat will work.

If you have never used a baking mat I promise you they are worth every penny. You will never go back to parchment again!

How to Make Flourless Monster Cookies

First, preheat oven to 350°F and line a jelly roll pan or large cookie sheet with parchment paper or a baking mat (a baking mat works best when spreading the dough.

Next, in a large bowl, cream together the brown sugar, granulated sugar, peanut butter, and butter until light and fluffy. Beat in the eggs and vanilla extract.

Add in the oats and baking soda and mix until well combined.

For best results, use a stand mixer with a paddle attachment.

Stir in the M&Ms and chocolate chips, reserving about 1/4 cup for the top.

Spread the dough onto the prepared cookie sheet and press down evenly and lightly. Sprinkle the reserved M&Ms onto the dough, and bake for 17-19 minutes until slightly browned around the edges.

Let cool for 30-45 minutes before slicing. Do not overbake!

How to Store

Make monster cookie bars that stay fresh and delicious for days or even months!

  • Store the Flourless Monster Cookie bars in an airtight container on the counter for up to 5 days.
  • Freeze them in a freezer container or bag for up to 3 months.

With this simple guide, you can keep your monster cookie bars tasting just as delightful as when you first made them!

No Flour Monster Cookie Bars Recipe

No Flour Monster Cookie Bars

No Flour Monster Cookie Bars

Yield: 48

No Flour Monster Cookie Bars 


  • 1 cup packed brown sugar
  • 1 cup granulated sugar
  • 1/2 cup salted butter, softened, (1 stick)
  • 1 1/2 cups creamy peanut butter
  • 3 large eggs
  • 1 tablespoon vanilla extract
  • 1 1/2 cups quick oats
  • 3 cups old-fashioned oats
  • 1 teaspoon baking soda
  • 1 1/2 cups mini m&m's
  • 1 cup mini chocolate chips


  1. Heat oven to 350 degrees. Prepare a jelly roll pan or large cookie sheet by lining it with parchment paper or baking mat. (A baking mat works the best when spreading out dough. See the link in the blog post for the baking mats I use.)
  2. In large bowl add the brown sugar, granulated sugar, peanut butter, and butter. Then beat until pale in color and fluffy.
  3. Add the eggs and vanilla extract and continue to mix.
  4. Add in the oats and baking soda. If using a stand mixer use the paddle attachment. Otherwise you may want to mix by hand or wooden spoon.  The mix will be very thick.
  5. Set aside about 1/4 cup of M&Ms for the top. Add in the rest of the M&Ms and chocolate chips. Mix together until well blended.
  6. Dump onto your baking mat lined cookie sheet and spread out. Sprinkle the reserved M&M's on top. Press down into dough.
  7. Bake for 17-19 minutes. Let cool for 30 to 45 mins before slicing.  Do not overcook.  It should brown slightly around edges.
Nutrition Information:
Yield: 48 Serving Size: 1 grams
Amount Per Serving: Calories: 177Total Fat: 9gSaturated Fat: 4gTrans Fat: 0gUnsaturated Fat: 4gCholesterol: 18mgSodium: 96mgCarbohydrates: 22gFiber: 2gSugar: 15gProtein: 4g

All amounts are estimates and DailyAppetite takes no responsibility for actual figures since calculations vary by packaging and supplier.

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No Flour Monster Cookie Bars Recipe

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