These without flour Monster Cookie Bars Made with oats, all-natural peanut butter, M&M’s and chocolate chips, they’re the perfect sweet treat. Enjoy!

Welcome to our take on monster cookie bars! They’re part monster cookies and part cookie bars baked to perfection for a chewy dessert. There are loads of these, so a great sweet treat to bring to a get together or to enjoy a snack with family on the go.
PS: Be sure to try our Monster Cookie Protein Balls!
What are Monster Cookie Bars?
Monster Cookie Bars are like monster cookies, only in bar form. They’re made with oatmeal, peanut butter, M&Ms, and chocolate chips.
We all love good monster cookies here in the Midwest, and this recipe is basically a giant cake pan with monster cookies baked and then sliced into bars. Can it get any tastier!?
Why You’ll Love Them!
They are without flour: These monster cookie bars are flour-free and gluten-free thanks to the quick-cooking oatmeal.
All Natural Peanut Butter: We’re big fans of using all-natural, drip-free peanut butter with one ingredient – PEANUTS, and without the added fillers often found in many nut butters. Smucker’s All-Natural is our top choice.
No granulated sugar: Instead of using white granulated sugar like many cookies and cookie bars, we use light brown sugar for these cookies. Feel free to substitute coconut sugar 1:1 if that’s your jam!
Dark Chocolate Chips and M&Ms: We love the flavor that dark or semi-sweet chocolate chips add to these bars (rather than milk chocolate chips). We also used M&M’s to give them a deliciously chocolatey crunch. They’re monster cookies, after all! What else could you use?
- Butterscotch chips
- Peanut Butter Chips
- White chocolate chips
- raisins
Try it!
Flourless Monster Cookies
These without flour monster cookies are your new favorite dessert! Made with oatmeal, peanut butter, chocolate chips and M&Ms, these cookies are packed with all the good stuff.
Get the recipe

What you need for monster bars
These monster bars come with a short list of ingredients that you probably already have on hand. Here are the 9 ingredients you need and a few pro tips for ingredient swaps you might be thinking about:
- Quick Cooking Oats: We recommend NOT using anything other than rolled oats in this recipe. We’ve found that oatmeal or rolled oats soaks up too much of the wet ingredients and results in dry bars.
- All natural, dripping peanut butter
- maple syrup
- Melted butter: We do not recommend substituting any other fat for the butter as we have not tested it.
- eggs
- Light Brown Sugar: You can also substitute coconut sugar in a 1:1 ratio if you like!
- baking powder
- M&M’s
- Semi-sweet chocolate chips

How to make Monster Cookie Bars
For the full recipe, Scroll down to the recipe card for a list of ingredients and directions.
Preheat and prepare
First, preheat the oven to 350°F and spray a 9×13 inch casserole dish with cooking spray.
mix ingredients
The great thing about these bars is that you don’t have to mix the wet and dry ingredients separately. A bowl baby! Put in a large bowl:
- Oats
- peanut butter
- maple syrup
- melted butter
- eggs
- Brown sugar
- baking powder
And mix with a wooden spoon. The batter should be thick like cookie dough. Then add the M&Ms and chocolate chips and mix again. When you mix in the M&M’s and chocolate chips last, make sure the warm, melted butter doesn’t melt them.
Pour the batter into the casserole dish
Place the cookie dough in the baking dish and use your wooden spoon (or your hands) to press the dough firmly and flat into the baking dish.

Bake
Bake at 180°C for about 17 to 20 minutes or until the sides are golden brown and the center is set.
Let cool and enjoy!
Allow the Monster Cookie Bars to cool for at least 30 minutes to 1 hour before slicing and serving. This gives them time to cool completely and ensures a clean cut of each individual bar. Yummy.

storage
Let the cookie bars cool completely. Then place in an airtight container or gallon-sized bag and store in a cool, dark place for up to 5 days. If your sheet pan has a lid, you can place the monster cookie bars right in the sheet pan for storage.
Can I Freeze Monster Cookie Bars?
You have two options for freezing these monster cookie bars.
dough -> Wrap the dough in plastic wrap, then place in a gallon-size freezer-safe bag. Remove as much air as possible and freeze for up to 3 months.
Cookies -> Allow the bars of monster cookies to cool completely, then cut into individual bars, then place in a freezer-safe gallon-sized bag. Remove as much air as possible and freeze for up to 3 months.


Monster Cookie Bars
These without flour Monster Cookie Bars are packed with oatmeal, all-natural peanut butter, M&Ms and chocolate chips, making them the perfect sweet treat. Enjoy!
Preparation:20 protocol
Cook:20 protocol
In total:40 protocol
instructions
-
First, preheat the oven to 350°F and spray a 9×13 inch casserole dish with cooking spray.
-
In a large bowl, combine oatmeal, peanut butter, maple syrup, melted butter, eggs, brown sugar, and baking powder and mix together with a wooden spoon. The batter should be thick like cookie dough.
-
Then add M&Ms and chocolate chips. Mix again.
-
Place the batter in the casserole dish and use your wooden spoon (or your hands) to press the batter firmly into the casserole dish.
-
Bake at 180°C for about 17 to 20 minutes or until edges are golden brown and firm to the touch.
-
Allow the monster bars to cool for at least 30 minutes to 1 hour before slicing and serving.
nutritional information
Calories: 389kcal Carbohydrates: 49G Protein: 8thG Fat: 20G Fiber: 5G Sugar: 18G
