Classic monster cookies baked into brownie bars for a yummy, over-the-top treat! These Monster Cookie Brownies are super easy to whip up using brownie mix, peanut butter cookie mix, and plenty of chocolate candies.

These bars bring me joy just looking at them! They are so fun, happy, and festive and they taste AMAZING! Imagine red/blue candies for 4th of July, red/white/pink for Valentine’s Day, red/green for Christmas…you caught on, right?!

Anyways, these M&M Cookie Brownie Bars are so yummy and could not be easier to make! They are simple enough for a quick at-home treat, yet look so fun for potlucks or dinner parties.

Love easy desserts? Check out these popular treats that come together in minutes: No Bake Cheesecake Bites, Chocolate Cheesecake Mousse, and Rolo-Stuffed Sugar Cookies.

INGREDIENTS

These Monster Brownie Cookies are made super easy with brownie and cookie mixes. You could make it even easier with pre-made peanut butter cookie dough. Just mix up all the ingredients, add dollops of cookie dough to the brownie batter, and bake! So easy the kids can help.

• 1 box, brownie mix, plus ingredients to make brownies
• 1 package, peanut butter cookie mix (rec Pillsbury brand), plus ingredients for mix OR pre-made peanut butter cookie dough
• chocolate chips
• mini m&m’s

HOW TO MAKE MONSTER COOKIE BROWNIES:

1. Preheat oven to 350 degrees. Prep a 9 x 11″ pan with non-stick spray.
2. Using mixer, combine brownie mix ingredients. Pour batter into pan, set aside.
3. Using mixer or spoon, stir together ingredients for peanut butter cookie mix. ***see note***
4. Add all of chocolate chips and half of M&M’s to bowl, and stir to combine. Scoop out a handful of cookie dough, roll into ball, and flatten it out. Lay atop the brownie batter. Using this technique, add rest of cookie dough to brownie pan.
5. Sprinkle the remaining M&M’s onto exposed brownie batter.
6. Bake for 25-30 minutes, or until a toothpick comes out mostly clean. Allow to cool for 10 minutes before serving.

variations

• Often monster cookies are made with quick oats as a mix-in, but that can make the cookies dry, which is why this recipe does not contain them. However, if you love oats in monster cookies, then feel free to add them!
• You can use peanut butter cookie dough mix, pre-made peanut butter cookie dough, or make the dough from scratch. Totally up to you.
• Make Halloween Monster Brownies or Monster Mash Brownies by replacing the M&M’s with edible candy “eyeballs”. So fun!

expert tips

• To check if the cookie/brownies are done, insert a toothpick in the center of the pan. It should come out mostly clean when the brownies are done.
• Be sure to leave half the M&M’s out to sprinkle on the brownie batter before you place in the oven. This makes it easier to see the M&M’s and adds a fun pop of color
• Use nonstick spray on pan for easier clean-up

handy tools to easily make these brownie bars:

• mixer – mixing, blending, whipping…THE BEST
• mixing bowl – microwave safe, 10 sizes

storage

• These Monster Cookie Brownies will keep at room temperature for 3-5 days or in the fridge for up to a week.
• Bars should be well-covered with plastic wrap or aluminum foil to prevent them from becoming stale.
• If you refrigerate them, you may want to place bars on a microwave-safe plate and reheat them for about 20 seconds before serving.

FAQ

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Yield: 1 dozen

Monster Cookie Brownies

Prep Time: 15 minutes

Cook Time: 25 minutes

Total Time: 40 minutes

Classic monster cookies baked into brownie bars for a yummy, over-the-top treat! Super easy to whip up using brownie mix, peanut butter cookie mix, and plenty of chocolate candies.

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Ingredients

• 1 box, brownie mix, plus ingredients to make brownies (typically 1 egg and ⅓ cup veggie oil)
• 1 package, peanut butter cookie mix (rec Pillsbury brand), plus ingredients for mix (3 tablespoon oil, 1 egg) OR 8 oz pre-made peanut butter cookie dough
• ¼ cup chocolate chips
• ¼ cup mini m&m's (reserve half for topping batter in pan)

Instructions

1. Preheat oven to 350 degrees.
2. Prep a 9 x 11" pan with non-stick spray.
3. Using mixer, combine brownie mix ingredients.
4. Pour batter into pan, set aside.
5. Using mixer or spoon, stir together ingredients for peanut butter cookie mix. ***see note***
6. Add all of chocolate chips and half of M&M's to bowl, and stir to combine.
7. Scoop out a handful of cookie dough, roll into ball, and flatten it out. Lay atop the brownie batter. (See photo in blog post)
8. Using this technique, add rest of cookie dough to brownie pan.
9. Sprinkle the remaining M&M's onto exposed brownie batter.
10. Bake for 25-30 minutes, or until a toothpick comes out mostly clean.
11. Allow to cool for 10 minutes before serving.

Notes

***You will only need half of the peanut butter cookie dough that the mix makes. You can either use only half of the mix or make it all and bake the rest of the cookie dough on its own.

Variations

• Often monster cookies are made with quick oats as a mix-in, but that can make the cookies dry, which is why this recipe does not contain them. However, if you love oats in monster cookies, then feel free to add them!
• You can use peanut butter cookie dough mix, pre-made peanut butter cookie dough, or make the dough from scratch. Totally up to you.
• Make Halloween Monster Brownies or Monster Mash Brownies by replacing the M&M's with edible candy "eyeballs". So fun!

Expert Tips

• To check if the cookie/brownies are done, insert a toothpick in the center of the pan. It should come out mostly clean when the brownies are done.
• Be sure to leave half the M&M’s out to sprinkle on the brownie batter before you place in the oven. This makes it easier to see the M&M’s and adds a fun pop of color
• Use nonstick spray on pan for easier clean-up

handy tools to easily make these brownie bars:

• mixer – mixing, blending, whipping…THE BEST
• mixing bowl – microwave safe, 10 sizes

storage

• These Monster Cookie Brownies will keep at room temperature for 3-5 days or in the fridge for up to a week.
• Bars should be well-covered with plastic wrap or aluminum foil to prevent them from becoming stale.
• If you refrigerate them, you may want to place bars on a microwave-safe plate and reheat them for about 20 seconds before serving.

Nutrition Information:

Yield:

12

Serving Size:

1
Amount Per Serving: Calories: 250Total Fat: 14gSaturated Fat: 6gTrans Fat: 0gUnsaturated Fat: 7gCholesterol: 18mgSodium: 188mgCarbohydrates: 30gFiber: 1gSugar: 12gProtein: 3g

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Love these Monster Cookie Brownies as much as I do? Then you must try these Fruity Pebbles Cookies and these Nutella Cake Mix Cookies! So good!

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