Monster cookie brownies start with a boxed brownie mix and then topped with a homemade monster cookie dough. Two desserts in one! Milk chocolate brownies and monster cookies loaded with peanut butter, oats, chocolate chips, and m&m’s.
The other day my kids asked for a treat and I am not ever one to say no to baking with my kids. As usual, the treat ended up involving m&m’s! I might be in the minority here but I keep a stock supply of mini m&m’s in the pantry, haha! My life will be complete when Costco decided to sell big giant bags of the mini m&m’s. Because right now my “hoard all the mini m&m’s” practice is a bit expensive….. those small bags of them are like $4.00.
Which in my world is totally worth it because then you can make treats like these monster cookie brownies that combine the best desserts into one bar. Brownies + monster cookies ♥
The base is a milk chocolate boxed brownie mix, which is why these are so easy to make. I know some don’t like the idea of using a boxed brownie mix and that’s ok. Make your favorite homemade brownies or try our very favorite recipe for homemade brownies. Just make sure that you make a recipe that yields a 9×13 pan of brownies, if you choose to make your own.
The only boxed brownie mix I will buy is the Pillsbury brand. I don’t know what it is about that specific one, but they always turn out so good. I am not a fan of really wet, fudgey brownies and the Pillsbury ones cook up perfectly. But again, that’s just me, and you can use any box. I am sure I have used other brownie mixes when making these. They will turn out fabulous regardless 🙂
Because this recipe only uses 1/4 cup mini m&m’s and chocolate chips you will have plenty leftover to make our very favorite recipe for monster cookies or you can also try out these no flour monster cookie bars too!
If you love recipes that use shortcuts, like this boxed brownie mix one, then be sure and try out my recipe for cake mix monster cookies. Just as easy as today’s recipe but the base is a buttery, yellow cake mix!
I feel like I say this every time I post a monster type cookie recipe but I highly suggest you use the miniature chocolate chips and mini m&m’s that the recipe calls for. I feel like the larger size of the regular chocolate chips and m&m’s is overwhelming in most baked goods. Like the chunks are too big or som]ething compared to the other ingredients.
So just trust me on this one and get the mini sizes. And be sure to save some of the m&m’s to sprinkle on top of the brownies before baking. It just adds some color and makes it look pretty.
How to make monster cookie brownies the easy way!
- Prepare a box of milk chocolate brownies according to the package directions. Most call for water, oil, and eggs. Stir that together and then pour it into a 9×13 baking pan that has been sprayed with cooking spray or lined with parchment paper. You can even line it with tin foil just be sure to spray the tin foil with some cooking spray.
- In a small mixing bowl prepare the monster cookie dough. You won’t even need a mixer for this! Just a fork is all you need.
- There are two ways you can spread the cookie dough onto the brownies. Dollop it on or take a scoop of dough and flatten it (kind of) with your hands and then lay it over top the brownie batter. I did it this way and while it’s messy, it does yield a more even layer of monster cookie dough on top of the brownies. Either way works!
- Sprinkle a few extra m&m’s on top and bake.
- Just as with any brownies, you want to let them cool for at least 30 minutes to 1 hour so that they can set up and stay together when you cut them into squares.
If you love all treats with m&m’s (like us!) then be sure to look through this roundup of THE BEST recipes with m&m’s!
Easy Monster Cookie 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)
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.
Make sure that your brownie mix is for a 9x13 baking pan. I think on some boxes it's called 'family size' or just follow the recommended ounces size in the recipe.
Linking this recipe at the weekend potluck
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