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    Home » Cookies

    The BEST Chewy Monster Cookies

    author bio
    Updated: Apr 9, 2025 by christina.marsigliese · 56 Comments
    Jump to Recipe

    If there was ever a cookie recipe that can make you feel like a kid again while simultaneously thinking you're being healthy-ish, it would be my Best Monster Cookie Recipe! These Monster Cookies are super chewy, incredibly delicious from nutty peanut butter and rolled oats with big puddles of melty dark chocolate and an assortment of M&M's. Warning: they are highly addictive! I found it very difficult to stop eating these. The chewiness of the cookie dough combined with the sweet/salty peanut butter and crunch from the candy-coated chocolate is all just so fun to eat. I think what makes this recipe stand out from the rest is the texture - they really are perfectly chewy and they stay that way for days!

    the best monster cookies on cooling rack

    WHAT ARE MONSTER COOKIES?

    Monster cookies always have three main ingredients: peanut butter, oats and colorful candy-coated chocolate. They are big, thick and chunky with a chewy texture and always contain oats. They're similar to a kitchen sink cookie, except they're more fun!

    the best monster cookies on cooling rack

    WHY THIS RECIPE WORKS

    • Chewy oatmeal cookies - these monster cookies have the most delightful chewy texture and they stay chewy forever! I mean... after a week they were still so chewy for me.
    • Chocolate chunk oatmeal cookies - big chunks of dark chocolate turn into lovely glistening puddles which make these Monster cookies stand out from the rest.
    • M&M cookies - you can't make Monster Cookies without candy-coated chocolate and my favorite is M&M's. If you use Smarties, I might judge you (I'm very passionate about this debate!)
    • Delicious peanut butter flavor - just the right amount of peanut butter makes these outstanding oatmeal cookies without overpowering the taste of the oats.
    the best monster cookies with bite

    INGREDIENTS FOR THE BEST MONSTER COOKIE RECIPE

    Here are some notes on some of the key ingredients for this recipe. For a full list of ingredients and measurements, scroll down to the recipe card at the bottom of this post.

    • Unsalted butter - there's no substitute for butter in delicious homemade cookies for me. If you only have salted butter, then reduce the added salt by half.
    • Peanut butter - this recipe works best with smooth or creamy peanut butter, and I like to use the regular emulsified type. If you use natural peanut butter they will be slightly more crumbly.
    • Brown sugar - I like to use light brown sugar for this recipe so the taste of the peanut butter and oats still shines. You can also use dark brown sugar.
    • Rolled oats - this recipe is designed to use rolled oats. If you use quick oats the cookies will be too crumbly and drier because quick oats absorb more moisture. They will also be thicker.
    • Honey - honey is the key ingredient to make sure these cookies stay nice and chewy! Do not leave it out.
    • Pure vanilla extract - vanilla is essential to making delicious cookies. I like this Madagascar Bourbon Vanilla extract.
    • Dark chocolate - this recipe works best with chopped dark chocolate from a bar or block of chocolate. It creates irregular chunks that melt more smoothly into the cookie dough.
    • Candy-covered chocolate - they wouldn't be Monster Cookies without them! You can use M&Ms or just generic candy-coated chocolate pieces.
    the best monster cookies recipe ingredients
    the best gooey monster cookies stacked

    STEP-BY-STEP INSTRUCTIONS FOR BEST MONSTER COOKIE RECIPE

    • STEP 1). Combine dry ingredients. Add all of the dry ingredients except for the oats in a large bowl and whisk to blend evenly.
    • STEP 2). Cream butter and sugar. Beat together the butter with brown sugar until smooth and a bit fluffy.
    • STEP 3). Mix in peanut butter and honey. Add in peanut butter and honey and mix until well combined.
    • STEP 4). Mix in egg. Add the egg and mix well until evenly incorporated then mix in vanilla.
    • STEP 5). Mix in oats. Add the oats and mix them in.
    • STEP 6). Add dry ingredients. Add the flour mixture and fold it in until just combined.
    • STEP 7). Add the mix-ins. Add the chocolate chunks and M&M's and fold them in.
    • STEP 8). Chill the dough. Cover the dough and refrigerate for about 1 hour.
    • STEP 9). BAKE. Scoop heaped 2 tablespoon portions of dough and roll into smooth balls. Place them onto lined baking sheets and bake until golden and still soft in the middle!
    the best monster cookies

    EXPERT BAKING TIPS

    • Add the oats to the wet mixture. This allows the oats to get a head start on hydrating which will give the cookies a chewier texture.
    • Refrigerate the cookie dough. Even 30 minutes will improve the taste and texture of these cookies. Oats need time to soften and absorb some moisture so that they bake into the cookie dough rather than remain hard.
    • Leave plenty of space. For best results, bake 6 to 8 cookies per tray so there is room for spreading and also room for the hot air to circulate around the dough balls and brown the edges nicely.
    the best monster cookies with melty chocolate

    RECIPE FAQ

    Do I need to chill the cookie dough?

    You can make these cookies without chilling the dough, but I promise it's worth it. Giving the cookie dough time to rest and chill in the fridge allows the oats and flour to fully hydrate. This produces thicker, chewier cookies. Even 30 minutes will do in a hurry.

    Why did my cookies spread too much or why did my cookies come out flat?

    If your cookies spread a lot, then it could be that there was not the right amount of flour added. Too little flour will mean the cookies will not have enough structure to hold their shape and the dough will be too wet. The best way to measure the flour is using a scale to ensure you use the right amount. If you skip the chilling time, the cookie dough will spread more as well.

    Can I use quick oats to make monster cookies?

    This recipe for calls for rolled oats which provide wonderful texture and the right amount of spread in this cookie dough. You can use quick oats, however they will absorb more moisture and these cookies will turn out thicker (they will spread less).

    How do I store Monster cookies?

    These cookies are best stored at room temperature in an airtight container for up to a week.

    stack of the best monster cookies
    How to make chewy monster cookies?

    These cookies stay chewy with a tablespoon of honey. Honey is a "humectant" and that's a technical term for compounds or ingredients that hold onto water very tightly. This prevents excessive moisture loss from the cookie so that the moisture stays IN the cookie.

    Can I add nuts to this monster cookie recipe?

    Yes! You can add ½ cup of chopped almonds, walnuts or pecans . Peanuts would also be delicious!

    Can I freeze Monster cookies?

    Yes, just place the cooled cookies in a resealable freezer bag and freeze for up to 3 months. They just about 20 minutes to thaw.

    the best monster cookies with bite

    If you love cookies, check out these recipes!

    Chewy Pumpkin Chocolate Chip Cookies
    The BEST Chewy Pumpkin Cookies
    Chewy Brown Butter Snickerdoodles Cookies
    Brown Butter M&M Cookies Recipe
    Lemon Blueberry Cookies with White Chocolate Chunks
    Coffee Pecan Chocolate Chip Cookies
    Double Peanut Butter Chocolate Chunk Cookies
    Hazelnut Double Chocolate Chunk Cookies
    THE BEST Chewy Chocolate Chip Cookies – Bakery Style!
    the best monster cookies
    the best monster cookies

    Video

    The BEST Chewy Monster Cookies

    Christina Marsigliese
    the best monster cookies recipe
    These are the ULTIMATE chewy Monster Cookies! They're big fat oatmeal cookies with peanut butter, m&m's and chocolate chips!
    4.96 from 23 votes
    Print Recipe Pin Recipe
    Prep Time 10 minutes mins
    Cook Time 12 minutes mins
    Servings 16 cookies

    Ingredients
      

    • ¾ cup 105g all-purpose flour
    • ½ teaspoon baking soda
    • ½ teaspoon baking powder
    • ½ teaspoon salt
    • ½ cup 113g unsalted butter, softened
    • ¾ cup 165g packed light brown sugar
    • ¼ cup 60ml smooth regular peanut butter
    • 1 tablespoon 15ml honey
    • 1 large egg at room temperature
    • 1 teaspoon 5ml pure vanilla extract
    • 1 cup 100g large flake rolled oats
    • ⅔ cup 113g dark chocolate chunks
    • ⅓ cup 85g regular M&M's or other candy coated chocolate
    • ⅓ cup 85g mini M&M's or other candy coated chocolate

    Instructions
     

    • Combine flour, baking soda, baking powder and salt in a medium bowl and whisk to blend evenly.
    • Combine soft butter and brown sugar in a large bowl and "cream" it together with a spatula until evenly blended, smooth and a bit fluffy. The mixture will look like fluffy wet sand. Mix in peanut butter, then mix in honey. Add the egg and vanilla and mix until well combined. Mix in oats.
    • Add the flour mixture to the butter mixture and fold it in until it is just combined. Add chocolate chunk and both types of M&M's and fold them in until evenly distributed.
    • Place a piece of plastic wrap directly on the surface of the dough in the bowl and refrigerate for 30 minutes.
    • Preheat your oven to 350°F. Line two large cookie sheets with parchment paper and set aside.
    • Scoop up about 2 tablespoons of dough and roll into balls. Place them onto prepared baking sheets spacing them at least 2 inches apart. Bake for 10-12 minutes until lightly golden around the edges but still slightly soft in the center (they will set as they cool). Let cookies cool for 1 minute on the baking sheets, then transfer them individually to a wire rack to finish cooling.
    Keyword chocolate, cookies, oatmeal, oatmeal cookies, oats

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    Reader Interactions

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      Recipe Rating




    1. Manvi

      May 04, 2026 at 3:21 pm

      Hi Christina,

      I tried your brown butter chocolate chip cookies recipe and they were so so yummy. We finished more than half the batch the same day between the two of us at home haha. Thank you. Will subbing soft butter for brown butter be okay for this recipe? I fell in love with brown butter with your chocolate chip recipe so just wondering. Thank you 🙂

      Reply
      • christina.marsigliese

        May 05, 2026 at 1:24 am

        Thanks Manvi! I have not tested that in this recipe, but you will need to make adjustments to achieve the same texture. You can try adding 1 tablespoon of milk to make up for the moisture lost from browning the butter.

        Reply
    2. Lolly

      February 21, 2026 at 10:03 pm

      5 stars
      Came back to comment because omg these were amazing I took them to a family gathering today and everyone was messaging me saying that the cookies were so good, thank you for the overnight tips I think I will do this every time they came out so soft and gooey. Definitely trying out future cookie recipes form your page!

      Reply
      • christina.marsigliese

        February 22, 2026 at 3:22 am

        Thank you so much Lolly! Glad everyone enjoyed the cookies! 🙂

        Reply
    3. Lolly

      February 20, 2026 at 5:04 am

      Can I prep these and leave them over night in the fridge will it change the texture?

      Reply
      • christina.marsigliese

        February 21, 2026 at 2:57 am

        Hi Lolly! Yes you can, but they will be a little thicker. Be sure to wrap the dough well so it doesn't dry out and bring it to room temp before portioning and baking.

        Reply
    4. Laura

      February 17, 2026 at 7:54 pm

      Hi. My son really wants me to make him these monster cookies but he really hates peanut butter. Is there something I can substitute it with or can I just leave it out? Or will that ruin the flavour/texture of the cookie. We live in the UK.

      Reply
      • christina.marsigliese

        February 18, 2026 at 2:53 am

        Hi Laura! You can try substituting with another nut or seed butter. If you leave it out the cookies will be more crumbly.

        Reply
    5. Savannah

      December 14, 2025 at 8:41 pm

      5 stars
      I searched through 20+ monster cookie recipes before finally landing on this one since it was my first time baking them. My husband loves monster cookies and while I usually buy them from our local Amish store, I’m not a fan of some of the ingredients they use…so I decided to try making my own. I followed this recipe exactly as written, with the exception of using unbleached, glyphosate-free flour and rolled oats, natural peanut butter and all organic ingredients and I substituted M&Ms with Unreal Gems. These may be the best cookies I’ve ever baked. Truly a no-fail monster cookie recipe and it’s officially going into our weekly cookie rotation. Thank you SO much for sharing your recipe and your thorough instructions!

      Reply
      • christina.marsigliese

        December 15, 2025 at 3:08 am

        You are welcome Savannah! I'm so glad you enjoyed the recipe 🙂

        Reply
      • Andreea

        January 22, 2026 at 6:11 pm

        5 stars
        The best cookies I ever made! Thank you for the recipe ❤️🤗

        Reply
        • christina.marsigliese

          January 23, 2026 at 4:07 am

          You are welcome Andreea! I'm so glad you enjoyed the cookies 🙂

    6. Julie von Pertz

      June 08, 2025 at 12:47 am

      Any suggestions on adjusting the ingredients to make a larger batch?

      Reply
    7. Daddy K

      May 13, 2025 at 7:57 pm

      ?? I don't see an option to convert to Standard "cup" measurements??

      Reply
      • christina.marsigliese

        May 15, 2025 at 2:56 am

        Hi there, cup measurements are there in the recipe card.

        Reply
    8. Amber

      May 08, 2025 at 6:21 pm

      5 stars
      I love monster cookies but this recipe is absolutely the BEST!! I follow it exactly every time and my (grown adult) kids beg for more !! Thank you for sharing the world’s best recipe!! You are awesome!!

      Reply
    9. kori

      December 18, 2024 at 5:34 pm

      were making it now, and we are excited, the recipe instructions did not mention when to put in the oats, teaching a 10 year old and he was confused. we added to the dry, thank you

      Reply
      • christina.marsigliese

        December 18, 2024 at 9:14 pm

        Hi Kori, it says to mix in the oats in Step 2.

        Reply
    « Older Comments

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