How to make soft and chewy monster cookies from scratch, loaded with peanut butter, oats, M&M's, and chocolate chips. Easy dessert recipe you can easily customize for Halloween and other holidays. But watch out, cuz they'll disappear fast!
Monster chocolate chip cookies made with loads of chocolate are one of my favorite cookies. Partly because they remind me of a childhood neighbor and partly because they're just so soft and chewy.
When I was a kid, my neighbor would make the most delicious soft and chewy monster cookies filled with oatmeal, peanut butter, peanut butter chips, chocolate chips, and M&M's. I mean, she loaded those puppies up with all kinds of sweet chocolaty goodness.
Why You'll Love M&M Monster Cookies
There are a handful of reasons to love this scrumptious monster cookies recipe…
- They are easily customizable… You can make them festive for any occasion. Halloween? Add a spooky touch with candy eyeballs. Christmas? Use Christmas M&M's that are red and green. Easter? Use pastel colored M&M's.
- These cookies are especially fun to make with kids, and this is an easy recipe for that exact purpose.
- You can add other mix-ins besides chocolate chips and M&M's. Try Snickers bars, Reese's Pieces, Reese's Peanut Butter cups, Milky Way, mini marshmallows, and more!
- They're thick, soft, and chewy. What's not to love about soft monster cookies that are also thick and chewy?
- They're very similar to another reader favorite oatmeal cookies recipe, oatmeal chocolate chip cookies.
Ingredients and Substitutions Notes
You'll need to gather a few ingredients to mix up this monster cookie dough…
- Butter – I prefer to use unsalted butter rather than salted when baking, so I can more easily control the amount of salt that goes into the recipe. Also, be sure to soften the butter, so it will mix well.
- Light Brown Sugar – Brown sugar is just one of the things that helps give these cookies their soft and chewy texture.
- Peanut Butter – You can use creamy or crunchy, but I highly recommend creamy, mainly because we're already adding other crispy ingredients that will give a lot of crunch. It is best to use a regular peanut butter that doesn't require stirring every time you use it. I do use Skippy Natural creamy peanut butter, but it only requires stirring upon opening the jar the first time around. The problem with other natural peanut butters is that all of the oil can be too much for the dough, and your cookies may spread more while baking.
- Egg – You'll need a large egg.
- Vanilla Extract
- All-Purpose Flour – I recommend using an unbleached all-purpose flour. If you want to make these cookies gluten-free, use a good gluten-free flour that bakes well; <<– the one I link to here is my go to.
- Baking Soda
- Sea Salt – I recommend Redmond Sea Salt.
- Oats – You can use quick oats or old-fashioned oats. Either kind of oatmeal will work just fine.
- Chocolate Chips – While I prefer semi-sweet chocolate chips, feel free to use milk chocolate chips or dark chocolate chips.
- Peanut Butter Chips
- M&M's – Feel free to use Reese's Pieces instead.
- Other Optional Candies – Crushed Mini Snickers, Reese's Peanut Butter Cups, or other candies. And candy eyeballs, especially if you're making these cookies for Halloween.
How to Make Chewy Monster Cookies
These cookies are really easy to make. Here's how to mix up the dough…
- In a large mixing bowl, cream, or mix together, the softened butter and brown sugar.
- Then mix the peanut butter into the butter sugar mixture.
- Add the egg and vanilla extract, mixing well.
- In a separate bowl, whisk together the flour, baking soda, and salt.
- Add the dry ingredients to the wet ingredients, mixing well.
- Mix the oats into the cookie dough.
- Add the chocolate chips, peanut butter chips, M&M's, and other candies (except candy eyeballs) into the dough, mixing everything together well.
- Using a cookie scoop, drop the cookies onto a cookie sheet.
- Bake at 375° F for about 8 to 10 minutes, or until the cookies are lightly golden and done.
- If using candy eyeballs, gently press the eyeballs into the tops of the cookies while they're hot, adding as many or as few as you want. This has a dual purpose… 1) Great for decorating Halloween cookies and 2) It allows you to gently press the cookie down into a flatter cookie while still warm.
- Remove the cookies to a wire rack to cool. Then serve with a nice mug of cold milk and enjoy!
Expert Tips and Recipe FAQ's
It's really not necessary for this cookie recipe. These cookies are already pretty chewy, and I prefer to just go ahead and bake the cookies while the dough is nice and soft.
There may be a few reasons… 1) If you use natural peanut butter, the extra oil can make the cookie dough spread flat while baking. 2) If your oven is too hot, the cookies may bake flatter, due to the butter in the dough melting too quickly. 3) Did you measure out the ingredients correctly? When measuring flour, it helps to spoon the flour into measuring cups, then use a knife's edge to scrape off extra flour.
Yes, you can. Spread the dough into a greased 9×13 baking dish, and bake for at least 20-25 minutes, probably longer, 'til the cookie bars are golden and a toothpick inserted in the center comes out clean.
Store then in an airtight container on the counter. They should keep for 4 to 5 days.
Yes, you can make them and freeze them. Just allow enough time for the cookies to thaw before serving time. You can also freeze the cookie dough; just be sure to wrap it in plastic wrap, as well as place in an airtight container or freezer bag so it doesn't get freezer burn. It should keep in the freezer for up to 3 months.
Really Yummy Mix-In Ideas for Monster Cookies
We touched on this just a bit in the ingredients section, but this cookie dough is really versatile, and there are several mix-ins you can add to make them even more bulky, sweet, and monster-like…
- Mini M&M's
- Crushed Mini Snickers
- Reese's Peanut Butter Cups
- Reese's Pieces
- White chocolate chips
- Butterscotch chips
- Chopped walnuts or pecans
- Bits of graham crackers, mini marshmallows, and chocolate chips to make s'more monster cookies
Just use your imagination; the sky's the limit with these cookies.
More Reader Favorite Cookie Recipes (and Cookie Bars Too)
If you love this monster cookies recipe, you'll love these cookie recipes too!
- Chewy peanut butter cookies
- Best Chocolate Chip Cookies Ever
- M&M cookies
- Peanut butter fingers
- Buckeye bars
- Grandma's oatmeal raisin cookies
More easy last minute Halloween ideas –>> 20+ Halloween treats – including Halloween brownies, party punch, cookies, no bake desserts, treats on a stick, Halloween cupcakes, and more! And if it's a costume you need, why not make a DIY Garfield costume?
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Chewy Monster Cookies
Ingredients
- 1/2 cup unsalted butter softened
- 1 cup light brown sugar
- 1/2 cup creamy peanut butter
- 1 large egg
- 1 teaspoon vanilla extract
- 1 1/8 cups all-purpose flour
- 3/4 teaspoon baking soda
- 1/2 teaspoon sea salt
- 1/2 cup rolled oats
- 1/4 cup semi-sweet chocolate chips
- 1/4 cup peanut butter chips
- 1/2 cup M&M'S
- 1/2 cup candy eyeballs optional
Instructions
- Pre-heat the oven to 375° F.
- Cream, or mix together, the butter and brown sugar.
- Mix the peanut butter into the creamed mixture.
- Add the egg and vanilla extract into the creamed mixture and mix well.
- In a separate bowl, whisk together the flour, baking soda, and salt.
- Add the dry ingredients to the wet ingredients, mixing well.
- Mix the oats into the cookie dough.
- Add the chocolate chips, peanut butter chips, M&M'S, and any other candies you want into the cookie dough, mixing everything together well.
- Using a cookie scoop, drop cookies onto a cookie sheet.
- Bake at 375° F for 8 to 10 minutes, or until the cookies are lightly golden and done.
- While the cookies are still on the cookie sheet, gently press the candy eyeballs into each cookie.*
- Remove the cookies to a wire rack to cool.
- Serve with a mug of ice cold milk!
Not only do these sound delicious but they are just so fun to look at. Pinned this for the holiday. Thanks for sharing at #HomeMattersParty
Thank you so much, Donna!