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Monster Cookie Brownies start with a boxed brownie mix and topped with a homemade monster cookie dough, with peanut butter, oats, mini chocolate chips and mini m&m’s candies. A mix between a brownie and a cookie! This easy dessert recipe is always a favorite and so yummy too!
Monster Cookie Brownies Recipe
These easy to make monster cookie brownies combine two of my very favorite things, brownies + monster cookies ♥.
Monster Cookies are an amazing mix of oats, peanut butter, chocolate chips, and m&m’s. The brownie base is just an easy box mix of brownies, you can of course make homemade brownies instead, and then it’s topped off with monster cookie dough that gets baked right in. So you basically have a brownie and a cookie on one bite!
Ingredients You Need
There are several ingredients you need for this recipe, but it’s easy to mix up, and of course the base is a boxed brownie mix and that is quick also! You just need the ingredients called for on the back of the brownie mix.
- Milk Chocolate Brownie Mix – You will need to make the brownies according to the package instructions. It normally calls for eggs, oil, and water.
- Butter
- Creamy Peanut Butter – For best results do not use the all-natural peanut butter. Stick with regular peanut butter like Jif, Skippy, or Peter Pan.
- Sugar
- Brown Sugar – I use light brown sugar for all my baking.
- Large
- Vanilla Extract
- All-Purpose Flour
- Quick Oats
- Baking Soda
- Salt – Regular, iodized table salt is what I use in this recipe. Kosher salt and sea salt will also work fine.
- Mini Chocolate Chips
- Mini M&M’s
How to Make Monster Cookie Brownies
To make this brownie recipe you’ll need two mixing bowls, some measuring cups and spoons, and a hand mixer. You can just mix the cookie dough mixture with a wooden spoon but I find it much easier to use a hand mixer.
Make the Brownies
- Prepare brownies according to the instructions on the back of the box. Do not bake them. Just make the batter and pour it into a 9×13 baking dish that has been sprayed with cooking spray or lined with parchment paper.
Monster Cookie Dough
- In a mixing bowl, with a hand mixer, beat together the softened butter and peanut butter until creamy.
- Add the sugars, egg, and vanilla extract. Mix until combined.
- Add the dry ingredients and mix just until combined.
- Add in the chocolate chips and m&m candies and stir together.
Monster Cookie Brownies
- Pour the brownie batter into the prepared 9×13 baking dish.
- Take some of the cookie dough and smash it into a flat shape (dough will be sticky but try your best) and lay it on top of the brownie batter. Continue on with the remaining cookie dough.
- Bake in the oven and let cool in the pan before cutting. If you cut them while hot, the brownies will fall apart and they won’t hold together well.
Tips For Success
Here are a few of my helpful tips that will hopefully make this recipe a success in your own kitchen.
- Mini Sized : I know some might be tempted to use regular chocolate chips and regular sized m&m’s. Which will work just fine. But, I highly suggest sticking with the mini sized chocolate chips and m&m’s for this recipe. I love the smaller chunks of chocolate throughout the brownie, rather than one big piece of chocolate. I think it also looks prettier with the small m&m’s because there is more of them.
- Peanut Butter : Don’t try to use all-natural peanut butter, it won’t work as well. Stick with regular peanut butter like Jif, Skippy, and Peter Pan. The all-natural peanut butter is much thicker, not as much oils, and therefore it turns baked goods really dry.
- Make It Pretty! : Save some of the mini chocolate chips and mini m&m’s, or just use additional, to sprinkle on top of the bars before baking. I usually just add extra and gently press them into the top of the brownies before baking.
- Tip For Easy Cutting : I love using the pre-cut parchment paper sheets when making brownies and bars. I spray the baking pan with cooking spray and then lay a pre-cut parchment paper sheet in the pan, vertically, so that way the bottom of the pan is covered but there is lots of extra hanging over the sides which makes it easy to pick up the bars when I’m ready to cut them.
How To Store Leftover Brownies
Leftover brownies will keep well, in an air-tight container, at room temperature for 4-5 days. If they last that long!
If you prefer cold brownies then they can also be stored in the fridge as well.
Can I Freeze Monster Cookie Brownies?
Yes you can freeze these monster cookie brownies! Prepare according to directions and let them cool completely to room temperature.
- Cut into squares and wrap each piece in tin foil. Place all the foil wrapped bars into a freezer safe container like a gallon-sized Ziploc bag and freeze for up to 1-2 months.
- You don’t have to wrap the squares of brownie in tin foil but I prefer to do that to avoid the brownies from sticking together as they freeze.
- I have also just put a brownie or two inside a sandwich Ziploc bag and stuck them in the freezer. I usually do this if I know they will be eaten fairly quickly.
Let frozen brownies thaw at room temperature for a little bit before you eat. You can also warm it up in the microwave for a few seconds.
You’ll Love These Monster Cookie Inspired Recipes
- Monster Cookie Energy Balls
- Reese’s Stuffed Monster Cookies
- No Flour Monster Cookie Bars
- Triple Peanut Butter Monster Cookies
- Monster Cookie Dough Cheeseball Dip
More Brownie Recipes to Make
- Easy Nutella Brownies
- Candy Bar Brownies
- Cake Mix Triple Fudge Reese’s Brownies
- Andes Mint Cookie Brownies
Easy Monster Cookie Brownies
Ingredients
Brownies
- 1 box (18.3 oz) milk chocolate brownie mix (plus ingredients called for on box)
Monster Cookie Dough
- 1/3 cup creamy peanut butter
- 2 tablespoons butter, softened
- 1/4 cup brown sugar
- 2 tablespoons granulated sugar
- 1 large egg
- 1/2 teaspoon vanilla extract
- 1/3 cup all-purpose flour
- 1/4 teaspoon baking soda
- 1/4 teaspoon salt
- 1/4 cup quick oats
- 1/4 cup miniature chocolate chips
- 1/4 cup mini m&m's (plus more for on top)
Instructions
- Heat oven to 350 degrees. Prepare a 9x13 baking pan and spray with cooking spray, line with parchment paper, or line with tin foil (be sure to spray the tin foil with spray if you use it).
- Prepare brownies according to the direction on the box. Pour brownie batter into the baking pan and set aside.
- In a mixing bowl, add the peanut butter and softened butter. Stir with a fork until combined. Add brown sugar, sugar, egg, and vanilla extract. Stir with the fork until combined and mixed together.
- Add the flour, baking soda, and salt. Stir just until combined. Add the quick oats, chocolate chips, and m&m's. Stir again until combined.
- Drop spoonful's of the monster cookie dough over the brownie batter OR you can use your hands, grab some cookie dough and flatten it out (as best you can) and lay it on top of the brownie batter. This is how I do it and it gets an even layer on top of the brownies. Either way works just fine!
- Bake for 25-35 minutes or until done in the center. Use a toothpick to make sure it's not wet in the center before pulling them out. Mine usually take around 30 minutes to cook to my liking.
- Let cool in the pan for 30 minutes to 1 hour and then cut into squares. Store any leftover covered at room temperature.
Notes
Nutrition
Did You Make This Recipe?
I'd love to see it! You can share it with me on @togetherasfamilyblog and follow on Pinterest @together-as-family-blog-recipes or Facebook @togetherasfamilyblog for more!
OMG this just makes me jealous at how good they look! I’ll definitely be trying this recipe very soon!
Thanks for sharing!
My doctor put me on a low carb diet. I was trying to see how my carbs is in the monster cookie brownies since I don’t find anything listed like carbs, calories, fat, etc… Can you please send me the list or tell me how much carbs is in this dessert?
Carbs 30 sugars 20 fats 8grams statrutade fats 3 grams calories 202. Cholesterol 13 mg
These are to die for!!! I baked them for about 14 minutes (my oven is very finicky) and they were perfect. These are the bars you’ll want to hide, otherwise you will gorge on them. They are much easier, and easily as tasty, as traditional Monster cookies. Thank you for sharing such a fantastic recipe!
Made these today! They are addicting! Easy recipe!
Loved these so much!! My children especially were thrilled!? I baked them a bit longer which was a mistake. It made them a bit dry but still fantastic!!
Super yummy! Mine baked in 30 minutes, and I didn’t have m&ms but there was plenty of chocolate from the brownies and chocolate chips. Highly recommended!
So amazing I made them twice this weekend. The first time I couldn’t find mini m&m’s they were still good but the minis make a huge difference. My oven bakes hot so I baked at 325 until the middle rose up and the edges had begun falling (secret to perfectly baked brownies). I have always loved Monster cookies and brownies this is a perfect combo!
Yes, I tell people all the time that when you bake the mini m&m’s make a huge difference. So glad you loved these.
I don’t understand all the good reviews. I made this recipe exactly as written but the brownie wasn’t even close to baked through. It was total goo but the cookie was getting too done. The brownie mix box says to bake for 45-50 minutes, but this recipe says 25-30 minutes. I feel like the brownie needs to be partially baked but the instructions don’t say that.
Allergic to peanuts, could this be done without the peanut butter?
It adds a good flavor and texture, could you us an alternative nut butter? Almond or sun butter would be great!