One Giant Monster M&M Cookie.

One giant peanut butter M&M cookie to cure even the largest peanut butter cookie craving! 

One giant peanut butter M&M cookie to cure even the largest peanut butter cookie craving!

Sometimes you just have a giant peanut butter craving. Mixed with a giant M&M craving, a giant chocolate craving, and a giant cookie craving. So… why fight it?

Before I left for St. Lucia last weekend (what a wonderful trip!!), I surprised Kevin with an extra large cookie when he got home from work.  No reason really – I just personally needed a large cookie and I knew he’d want to share. Although sharing something like this is rather difficult.  Perhaps I should be called fiancé-of-the-year.

One giant peanut butter M&M cookie to cure even the largest peanut butter cookie craving!

The thing is, I love making giant cookies!  And if you have been reading SBA for awhile, you may already know about my affinity for making (and eating) them. The giant cookies are perfect for sharing OR gobbling up all by yourself if you’re extra hungry.

You can make them in less than 25 minutes too! They are each completely oversized and ridiculous in the best way possible:

My giant cookie collection was just begging for a monster cookie. Not sure what a monster cookie is? It’s an oatmeal cookie with peanut butter, M&Ms, and chocolate chips. The monster cookies I prefer, however, are more like peanut butter cookies with oats, not oatmeal cookies with peanut butter.

Still with me?

One giant peanut butter M&M cookie to cure even the largest peanut butter cookie craving!

The cookie isn’t as large as a pizza pie. It’s about 4 regular size cookies combined into one. It’s thick, chewy, and completely irresistible. But that goes without saying, right? Just like my full batch of soft-baked monster cookies, today’s XXL monster cookie will stay soft for days. Well, that’s only if it lasts that long. And trust me, it won’t.

This recipe is like any cookie recipe, just downsized.  A few tablespoons of this, a few tablespoons of that. All of your usual monster cookie suspects: flour, oats, butter, peanut butter, white sugar, brown sugar, baking soda, chocolate chips, and egg. Oh and lots of M&Ms. A note for the egg: all you have to do is crack an egg, beat it, and use 2 Tablespoons of the beaten egg. The ingredients are mixed by hand – no electric mixer needed! That’s my kind of last minute dessert.

One giant peanut butter M&M cookie to cure even the largest peanut butter cookie craving!

If you like cookies, if you like peanut butter, if you like M&Ms, and if you have any sort of sweet tooth – what are you waiting for? 

Follow me on Instagram and tag #sallysbakingaddiction so I can see all the SBA recipes you make. 

1 Giant Monster M&M Cookie

Yield: 1 large cookie

Print Recipe

One giant peanut butter M&M cookie to cure even the largest peanut butter cookie craving!


  • 2 Tablespoons unsalted butter, softened
  • 2 Tablespoons granulated sugar
  • 2 Tablespoons light brown sugar, packed
  • 2 Tablespoons beaten egg (crack an egg, beat it, and use 2 Tbsp)
  • 1/2 teaspoon vanilla extract
  • 2 Tablespoons creamy peanut butter (if using natural peanut butter, use a thick no-stir variety)
  • 6 Tablespoons all-purpose flour (measured correctly)
  • 2 Tablespoons old-fashioned rolled oats (or quick oats)
  • 1/4 teaspoon baking soda
  • 1/8 teaspoon salt
  • 1/3 cup M&Ms
  • 2 Tablespoons milk or semi-sweet chocolate chips


Preheat oven to 325F degrees. Spray baking sheet with nonstick spray or line with a silicone baking mat. Set aside.

In a large mixing bowl, whisk the butter and sugars until creamed. Add egg and vanilla mixing until well combined. Stir in peanut butter then add flour, oats, baking soda and salt. Fold in M&Ms until combined. With a large spoon, scoop into a ball onto prepared baking sheet. The dough will be sticky. Make sure the cookie dough ball is tall and round. Press the chocolate chips into the top of the cookie.

Bake for 20-22 minutes, until edges are lightly browned. The center may appear undone, but it will set as the cookie cools. Let cool ON the baking sheet for 10-20 minutes.

Additional Notes:

*You may make four smaller cookies using this recipe. Just divide the dough into 4 smaller mounds on the cookie sheet rather than 1 large mound. Bake for 8-10 minutes.

*Want to make a whole batch of monster cookies? Here is my recipe for Soft-Baked Monster Cookies.

© Sally’s Baking Addiction. All images & content are copyright protected. Please do not use my images without prior permission. If you want to republish this recipe, please re-write the recipe in your own words, or link back to this post for the recipe.


So, are you a fan of monster cookies?

My recipe for soft-baked monster cookies is one of the most popular recipes on my website. Countless readers have made them and crown them the best cookies in the world. Trust me, you have to try them!

Monster Peanut Butter Cookies



181 Responses to “One Giant Monster M&M Cookie.”

  1. #
    Tashiaposted September 11, 2014 at 5:20 pm

    I just made this GIANT cookie- LOVE the recipe! I made a couple changes, and it still turned out great!
    -I didn’t have soft butter, so I microwaved the butter on defrost for 30 sec. Perfect.
    – I didn’t have m&m’s or chocolate, so I used coconut flakes and walnuts.

    I had to cook it for another 6 minutes to get it to cook through, and brown, but now it’s beautiful- golden brown, and perfectly shaped. Thank you!


  2. #
    ameerahposted September 18, 2014 at 8:04 am

    hi sally, i was wondering. can i make this without the PB and quick oats?


  3. #
    Mel Greenposted January 26, 2015 at 10:19 pm

    These cookies are SO good. I make these often for my husband and I! It is a pet peeve of mine when people comment just to say a recipe looks good, but don’t actually make the recipe. So I am here to say that these are the BEST!!! Sally, I would love it if you converted this recipe into a larger batch!


  4. #
    Barbra Donachyposted May 13, 2015 at 7:30 am

    Thanks for the terrific cookie recipe. It’s been a big hit. We adapted it a bit and blogged about it here:

    Greetings from Mongolia!
    Jack and Barbra


  5. #
    Leslieposted June 5, 2015 at 9:50 am

    Sally, you mentioned that you use a convection oven for all your baking. For this recipe, do you use 325 degrees even with the convention oven or 300 degrees? Then do you only cook it for 17 or 18 minutes? Thanks. 


    • Sallyreplied on June 5th, 2015 at 4:46 pm

      Leslie, I use a conventional oven. 325 for conventional for 20-22 minutes. Lower the temp and baking time for convection.


  6. #
    Annetteposted June 12, 2015 at 9:46 pm

    Hello Sally!

    I love your blog! I was looking at all of the delicious recipes and made the Snicker Doodles and Oatmeal M&Ms Cookies. Yum! I kept tooling around for other recipes and found these XXL cookies I would love to make these for the local farmers market — but I would like to make a “batch” of large cookies. Do you have a recipe for them in a larger batch?

    Thank you!



  7. #
    Cindyposted June 19, 2015 at 6:11 pm

    This cookie was OK. It was kind of dry. To be fair, I did not do the instructions that said cool for 10 minutes on the cookie sheet. I may make again and see if I can get it to be less dry and crumbly.


  8. #
    Nikita Patelposted June 23, 2015 at 12:14 am

    Hi Sally!
    It would be awesome if you could post a recipe for a giant plain chocolate chip cookie! 


    • Sallyreplied on June 23rd, 2015 at 11:33 am

      Nikita, you know what works? Make this chocolate cookie recipe but replace the 2 Tbsp of cocoa powder with flour!


  9. #
    Nairposted January 15, 2016 at 11:41 am

    Hi Sally loved this giant cookies and now I am obsessed  tried 3 baths trying to reduce the sugar dough! First did not flatten that much I used salted butter- 2nd double the recipe  made 15 muffin size cookies come out beautiful just forgot to take a picture . I also used one whole small size egg. Wondering why the cookie is not flattening?
    I love all your recipes  


  10. #
    Natalieposted February 3, 2016 at 10:48 pm

    Sally, I made this giant monster cookie and the giant chocolate-chocolate chip cookie this weekend. All I can say is WOW! I think I like this monster cookie even better than your recipe for the full batch. I didn’t have any M&Ms and was too lazy to go to the store, so I used a combo of white/dark/butterscotch chips to sort of make an “everything” cookie. The hubs freakin’ loved it, and he usually doesn’t get too jazzed about anything sweet. The chocolate one was great too, although I forgot to reduce salt since I used salted butter, so it was pretty salty — that was my own fault! It was still delicious, though. These giant cookie recipes are going to be my go-to now. There are only 2 of us, and when I bake an entire batch of cookies, I end up eating most of them myself. Hopefully the giant cookie recipes will help with my inner *need* to bake and not make me need to buy larger pants. Thanks again for all you do! :)


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