Monster M&M cookies! Soft, chewy, and loaded with oatmeal, peanut butter, M&M’s and chocolate chips. These one-bowl gluten-free cookies are a dream!

I remember all those years ago (six years, to be exact) when monster cookies were a new thing to me. A strange thing. An untasted thing.

A white tray with three oat M&M cookies and a few M&M's sprinkled around the side.

Once made and devoured, however, I wept for all the years when monster cookies were not part of my life. I’ve since made up for lost time and have the hips to prove it.

An M&M oat cookie on a piece of parchment with a tray of more cookies behind it.

Monster cookies, a strange name for a delightfully soft and chewy peanut butter oatmeal cookie studded with M&Ms and chocolate chips, are most definitely one of our favorite cookies ever.

If you happen to come over and take a peek in my {scary} freezer, there’s about a 98% chance you’ll find a batch or three of monster cookies hanging out in the depths just waiting to be warmed lightly in the microwave…or eaten straight from the freezer.

A tray of M&M oat cookies with additional M&M's sprinkled around the platter.

If there’s one thing I’ve learned in my long life, it’s that you’ll never regret having monster M&M cookies on hand for when you cannot go another minute without one. It’s also very surprising how often that happens. To me.

Flour-free, these cookies can easily be made gluten-free – just double check your oats to ensure they are certified gluten-free, and you are good to go.

A half of an M&M cookie on a piece of parchment with a few sprinkled M&M's on the side.

While the dough is a little stickier than traditional cookie dough, they still bake up soft and thick and chewy (no spreading, no cursing my name or the cookie’s name, just how I like it).

These cookies are perfect, and they just work. No flour and all.

So grab your ingredients and start mixing. One-bowl and minimal fuss, you are well on your way to having piping hot monster M&M cookies in your grubby little hands before that Netflix episode is over.

An M&M cookie on a piece of parchment paper with M&M's sprinkled on the side.

If you don’t have M&Ms, no worries. They can easily be swapped out for another kind of chip (peanut butter chips are dreamy in this cookie), or just go ahead and increase those chocolate chips.

Of course, without the M&Ms, it’s not entirely legal (says the food police) to call them “monster cookies,” but they’ll still be terribly delicious even if they are a matter-of-fact peanut butter, oatmeal, chocolate chip cookie.

Four M&M oat cookies lined up side-by-side on a white platter.

One Year Ago: Baked Garlic and Fontina Spaghetti
Two Years Ago: Curried Lentil and Sausage Soup with Toasted Almonds
Three Years Ago: Classic Crème Brulee


One-Bowl Monster M&M Cookies

4.74 stars (83 ratings)


  • 3 large eggs
  • 1 ¼ cups (265 g) packed light brown sugar
  • 1 cup (212 g) granulated sugar
  • ½ teaspoon salt
  • 2 teaspoons baking soda
  • 1 teaspoon vanilla extract
  • 1 ½ cups (383 g) creamy peanut butter
  • ½ cup (113 g) salted butter, softened
  • 4 ½ cups (450 g) quick cooking oats, (double check oats are gluten-free if making gluten-free cookies)
  • 1 cup (227 g) M&Ms
  • 1 cup (170 g) milk chocolate, semisweet, or bittersweet chocolate chips


  • Preheat the oven to 350 degrees F. Line cookie sheets with parchment paper, silpat liners or lightly grease with cooking spray.
  • In a large mixing bowl with a handheld electric mixer (or in a stand mixer fitted with the paddle attachment), add the eggs, brown sugar, and granulated sugar. Mix well.
  • Add the salt, baking soda, vanilla, peanut butter and butter. Mix until creamy and well combined, 1-2 minutes.
  • Stir in the oatmeal, M&Ms, and chocolate chips until combined. The dough will be sticky.
  • Scoop the dough into heaping tablespoon-sized balls (see note) and place about 2 inches apart on the cookie sheets. If you want the cookies thinner, flatten them slightly with the palm of your hand.
  • Bake the cookies for 8-10 minutes. Don’t overbake – the cookies should just be set and very lightly golden around the edges.
  • Let the cookies sit for 1-2 minutes on the cookie sheet before transferring to a cooling rack to cool completely. Store in a airtight container for 2 days (the baked cookies freeze well, also).


Gluten Free: keep in mind that if you want the cookies to be safely gluten-free, make sure your oats are certified gluten-free (it will say on the package if they are).
Oats: several commenters have successfully used old-fashioned oats (the cookies may spread a bit more). Or you could take your old-fashioned oats and process them lightly in a blender before using (measure after they have been blended a bit). 
Chips: also, lots of times when I make these, I sub in different kinds of chips. Peanut butter chips are dreamy (in addition to or in place of M&Ms or part of the chocolate chips). 
Cookie Size: many of you commented you’ve gotten a lot more than 2-3 dozen cookies out of this batch and that’s because you make your cookies small and I make mine not-small. Sometimes, I use my #40 medium cookie scoop which is about 1 1/2 to 2 tablespoons but a lot of time, I grab the #20 scoop which is 3 tablespoons or more. I mean, we’re going for monster cookie here, right?
Serving: 1 Cookie, Calories: 224kcal, Carbohydrates: 28g, Protein: 5g, Fat: 11g, Saturated Fat: 4g, Cholesterol: 22mg, Sodium: 178mg, Fiber: 2g, Sugar: 20g

Recipe Source: adapted slightly from a Paula Deen recipe on Food Network sent to me by Lucy J., a reader
Recipe first published November 2011; updated with new pictures, recipe notes and commentary.

A stack of M&M chocolate chip oat cookies on a white plate.