Soft and chewy monster cookies are loaded with oats, peanut butter, chocolate chips, and m&m's. These cookies are so fun to make and will disappear quickly so make a double batch!
These monster cookies are on regular rotation in our home and are the most requested by my family. There is a little something for everyone in these cookies, making them the perfect crowd-pleaser!
For more tasty desserts, check out our Southern Pecan Praline and our Chocolate Snowball Cookie recipes next!
Why You Will Love These Cookies!
- Easy to make. This cookie dough requires zero chill time so you can whip up a batch anytime!
- Packed with goodies. Oats, peanut butter, chocolate chips, and m&m's - need I say more?!
- Soft and chewy. These cookies bake up extra soft and chewy on the inside thanks to the peanut butter and oats!
- Totally customizable. Go crazy with different mix-ins to make these monster cookies all your own. You can even make them festive to match your favorite holiday!
Ingredients You Need To Make This Recipe
- Butter. For flavor and a soft, chewy texture. Be sure your butter is softened to room temperature.
- Peanut Butter. Adds delicious nutty flavor and structure to the dough.
- Granulated sugar. To sweeten the cookies.
- Brown sugar. For a caramel-like sweetness.
- Egg. To bind the dough.
- Vanilla extract. For flavor and depth. Use good quality vanilla - not vanilla flavoring!
- All-purpose flour. Use good-quality flour like Bob's Red Mill.
- Old-fashioned rolled oats. For texture. You can also use quick-cooking oats.
- Baking soda. To help the cookies rise.
- Salt. To highlight the flavors of the other ingredients.
- M&M milk chocolate candies. Sweet and crunchy mix-ins add texture!
- Semi-sweet chocolate chips. The more mix-ins and chocolate, the better!
How To Make This Recipe
- Preheat your oven to 350°F. Line a baking sheet with parchment paper or a silicone baking mat and set it aside.
- Add the flour, oats, baking powder, and salt to a medium mixing bowl and whisk together until combined. Set the flour mixture aside.
- Beat the butter, peanut butter, and sugars in the bowl of a stand mixer fitted with the paddle attachment, or in a large mixing bowl with a handheld electric mixer, until light and creamy, about 3 minutes. Start on low speed then gradually increase the speed to high.
- Add the egg and vanilla and beat on medium until completely mixed in. Add the flour mixture to the bowl with the butter mixture and beat until no more streaks of dry flour are visible. Start on low speed, then gradually increase the speed to medium-high, scraping down the sides and bottom of the bowl to ensure everything gets evenly mixed.
- Add the m&m's and chocolate chips to the bowl and beat on low until evenly mixed into the dough. The dough will be slightly crumbly.
- Using a cookie scoop, scoop about 3 tablespoons (60g) of dough into your palm, form it into a ball, and gently press the ball between your palms to flatten them into a cookie shape. Line the cookies on the baking sheet about an inch apart, and gently press a few more chocolate chips and m&m's into the tops of the cookies.
- Bake the cookies in the preheated oven on a center rack for 8 to 10 minutes, or until the bottoms just start to turn light golden brown.
- The cookies will look slightly underbaked and do not spread much at all while baking - that is exactly what you want! The cookies will continue to set as they cool and will be perfectly soft and chewy on the inside. Serve these cookies warm or at room temperature.
Variations and Substitutions
You can have so much fun with monster cookies by adding different mix-ins! Try adding some of the following to your cookies:
- Butterscotch chips
- Peanut butter chips
- White chocolate chips
- Chopped nuts
- Raisins or other dried fruits
What Are Monster Cookies?
Monster cookies are soft-baked cookies made with a variety of mix-ins, typically including oats, peanut butter, chocolate chips, and m&m's.
There are many monster cookie variations, some that contain no flour at all and some that contain more or less of the different ingredients, depending on the desired texture.
Monster cookies are essentially an epic mashup of peanut butter, oatmeal, and chocolate chip cookies in one and this recipe bakes up thick, soft, chewy, and irresistible!
Why Is My Dough So Crumbly?
While this cookie dough should turn out slightly crumbly, it should not be too crumbly to work with. If you have this problem, you most likely added too much flour to your dough.
Be sure to measure your flour by fluffing it, spooning it into your measuring cup, and leveling it off with a knife. For the most accurate measurement, weigh your flour with a kitchen scale.
Can This Cookie Dough Be Frozen?
Absolutely! This cookie dough can be shaped into a log, tightly wrapped in plastic wrap, and stored in the freezer for up to three months.
Thaw the dough in the refrigerator when ready to bake or slice the cookies and bake them from frozen.
Make-Ahead and Storing Instructions
This cookie dough can be made up to three days ahead of time and stored in the refrigerator until ready to bake.
Leftover monster cookies can be stored in an airtight container at room temperature for up to a week or frozen for up to 3 months.
Recommended Tools For This Recipe
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Soft and Chewy Monster Cookies
Equipment
Ingredients
- 1 ¾ cups all-purpose flour (215g), weighed or spooned and leveled
- ¾ cups old-fashioned rolled oats or quick cooking oats
- 1 teaspoon baking soda
- ½ teaspoon salt
- ½ cup butter 1 stick, unsalted, softened
- ½ cup creamy peanut butter
- ½ cup dark brown sugar
- ½ cup granulated sugar
- 1 large egg room temperature
- 1 ½ teaspoons vanilla extract not vanilla flavoring
- ¾ cup milk chocolate m&m's
- ½ cup semi sweet chocolate chips
Instructions
- Preheat your oven to 350°F. Line a baking sheet with parchment paper or a silicone baking mat and set it aside.
- Add the flour, oats, baking powder, and salt to a medium mixing bowl and whisk together until combined. Set the flour mixture aside.
- Beat the butter, peanut butter, and sugars in the bowl of a stand mixer fitted with the paddle attachment, or in a large mixing bowl with a handheld mixer, until light and creamy, about 3 minutes. Start on low speed then gradually increase the speed to high.
- Add the egg and vanilla and beat on medium until completely mixed in. Add the flour mixture to the bowl with the butter mixture and beat until no more streaks of dry flour are visible. Start on low speed, then gradually increase the speed to medium-high, scraping down the sides and bottom of the bowl to ensure everything gets evenly mixed.
- Add the m&m's and chocolate chips to the bowl and beat on low until evenly mixed into the dough. The dough will be slightly crumbly.
- Using a cookie scoop, scoop about 3 tablespoons (60g) of dough into your palm, form it into a ball, and gently press the ball between your palms to flatten them into a cookie shape. Line the cookies on the baking sheet about an inch apart, and gently press a few more chocolate chips and m&m's into the tops of the cookies.
- Bake the cookies in the preheated oven on a center rack for 8 to 10 minutes, or until the bottoms just start to turn light golden brown.
- The cookies will look slightly underbaked and do not spread much at all while baking - that is exactly what you want! The cookies will continue to set as they cool and will be perfectly soft and chewy on the inside. Serve these cookies warm or at room temperature.
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