These Monster Cookies are loaded with oats, peanut butter, chocolate chips, and M&M‘S. Seriously, what’s not to love about them? Definitely one of our favorite cookies ever!
Today is one of those days that I’d be just fine completely ignoring. You know, just pretend like it isn’t even happening.
Why?
Because it’s my 50th birthday and I’m not quite ready for it😩.
It’s bad enough that I’m turning 50, but because our country is sadly in the midst of a pandemic, I can’t even celebrate/commiserate with all of my family, or go on the trip my husband was going to take me on. The whole thing kind of stinks. But I’m trying to look on the bright side of things. I’m healthy, have an amazing husband and kids, an awesome family, and the most amazing lifelong friends. So yes, I hate the fact that I’m getting older, but I guess we all are, right?
Since it’s my birthday and cookies are my all time favorite thing ever, it’s only fitting that I share one of my all-time favorite cookie recipes today. I actually posted these Monster Cookies over six years ago and decided they were in much need of some new photos and updated instructions. I made a batch of these for our “girl’s 50th birthdays” trip with my high school girlfriends we took back in March. To say they loved them is a bit of an understatement.

I have always loved monster cookies (ok I love pretty much every cookie). They’re chock full of peanut butter, oatmeal, M&M’s and chocolate chips — does a cookie get any better than that? If I’m being honest, I don’t know if I love the dough more or the baked cookies. Oh and because there is no flour in these monster cookies, they’re gluten free which is an added bonus for some of you.
CAN I USE OLD-FASHIONED OATS INSTEAD OF QUICK OATS?
Quick oats are more finely cut whole oats and will give the monster cookies a more uniform texture. Also, because they’re finer, they act as a binder. It won’t be the end of the world if you use old-fashioned oats, the cookies may just spread a bit more. If you don’t have quick oats, you can pulse your whole oats in the food processor a few times to break them down.
HOW TO MAKE MONSTER COOKIES:
- Preheat oven to 350°F. Spray cookie sheet with nonstick spray, or line with parchment paper or a silpat liner.
- In the bowl of a stand mixer combine the peanut butter with the sugars and butter. Mix until well combined. Mix in the eggs and vanilla.
- Add baking soda, salt and oats and mix until well combined.
- Stir in the chocolate chips and M&M’s.
- Scoop large balls of dough (about 2 to 3 tablespoons) and place about 2 inches apart on the cookie sheets.
- Bake 9 to 11 minutes. Do not overbake.
- Cool for 5 minutes on cookie sheets until cookies are set. Transfer to a cooling rack.

HOW TO FREEZE MONSTER COOKIES:
- To freeze the dough, place cookie dough balls onto a silicone mat lined baking sheet. Place the baking sheet in the freezer until the cookies are frozen solid, about 1 hour.
- Remove the baking sheet from the freezer and transfer the frozen cookie dough balls to a ziplock freezer bag. Label the bag with baking directions. Freeze the cookie dough for up to 3 months.
- To bake frozen dough balls remove the dough from the freezer. Pre-heat the oven to 350ºF. Bake for 14-17 minutes. Frozen cookies may need to bake for 1-2 minutes longer.
- To freeze baked cookies, place them in a freezer Ziploc bag and seal tightly. Freeze for up to 3 months. P.S. A frozen monster cookie is one of the most delicious things ever!

MY SECRET FOR THESE COOKIES:
A lot of the recipes for Monster Cookies that I’ve seen over the years call for 1 cup of chocolate chips and 1 cup of M&M’s. You all should know me well enough by now to know that 1 cup of chocolate chips or anything like that in a cookie recipe is NOT enough. So I always put 2 cups of chocolate chips and 2 cups of M&M’s. You can adjust the amount to anything you’d like, but please don’t be like my dad and put one chocolate chip and one M&M in each cookie (I’m not even joking about that!).
ENJOY!
Print
Monster Cookies
- Total Time: 25 minutes
- Yield: 4 dozen 1x
Ingredients
- 1 1/2 cups peanut butter
- 1 cup brown sugar
- 1 cup granulated sugar
- 1 stick butter
- 3 eggs
- 1 teaspoon vanilla extract
- 2 teaspoons baking soda
- 1/2 teaspoon salt
- 4 1/2 cups quick cooking oats
- 1 cup M&Ms (I use 2 cups)
- 1 cup milk chocolate chips (I use 2 cups and always use Guittard!)
Instructions
- Preheat oven to 350°F. Spray cookie sheet with nonstick spray, or line with parchment paper or a silpat liner.
- In the bowl of a stand mixer fitted with the paddle attachment combine the peanut butter with the sugars and butter. Mix until well combined. Mix in the eggs and vanilla. Add baking soda, salt and oats and mix until well combined. Stir in the chocolate chips and M&M’s.
- Using a cookie scoop, scoop large balls of dough (about 2 to 3 tablespoons) and place about 2 inches apart on the cookie sheets.
- Bake 9 to 11 minutes. Do not overbake. If you want the cookies flatter, gently bang the cookie sheet a couple times on the counter after they come out of the oven. Cool for 5 minutes on cookie sheets until cookies are set. Transfer to wire racks; cool completely before storing in an airtight container.
- These cookies freeze really well.
Notes
- This cookie dough is really soft and sticky, so don’t think you’ve done something wrong.
- Prep Time: 15 minutes
- Cook Time: 10 minutes
- Category: Cookies
Originally published March 9, 2014

Jodi wishing you a wonderful 50th. You are the best blogger.
Thanks Teresa! It ended up being a great day, pandemic and all! Hope you’re doing well and hanging in there through all of this!❤️