These super soft and chewy monster cookies are such a fun baking project to make for Halloween (or any day really)! This recipe whips up in no time and features a no chill cookie dough - so you can get to digging in that much faster.
I've always wondered why they're called "monster" cookies - but there's no one answer I could find. Some people have guessed that it's because they kind of look like monsters - with the texture from the oats - which I think is just the cutest.
Maybe it's because they're scary, monstrously good? Oooorrr maybe it's because you'll look like a monster scarfing them all down - they're just that good!
Either way, there's no doubt they're delicious, and I can 100% envision the cookie monster making these a part of its diet.
what are monster cookies?
Monster cookies are like chocolate chip cookies' extra sibling. On top of all the classic cookie fixings in the dough, you have some added deliciousness in the form of oats, peanut butter, and m&m's.
what makes these chewy monster cookies so good?
- baking powder AND baking soda. Using both helps give these cookies their characteristically chewy texture.
- flavor. Oats, m&m's, and peanut butter in one cookie?! It's absolutely LOADED with flavor!
- texture. Did I mention these cookies are unbelievably soft and chewy??
- colors. It's super fun and colorful! You can also use different holiday colored m&m's to suit the season you're baking for - red & green for Christmas, orange & brown for Halloween, and so on!
- one bowl. Less washing, more eating!
the secret to extra chewy cookies...
Milk! A little added milk will yield extra chewy cookies! It acts a lot like an egg yolk - without the need of cracking another egg and running the risk of forgetting you had an egg white in the fridge (been there...)
Aside from that tweak, I also made a few other changes to make an even better cookie:
- flour: I used slightly more flour than oats to make sure the cookies held their shape well and weren't a crumbly, delicious mess.
- baking powder + soda: 1 heaping teaspoon of each gives these cookies an extra airy center, which becomes perfectly dense and chewy once it cools down and sinks slightly!
- brown sugar: a higher ratio of brown sugar to granulated also gives these cookies added moisture and softness - without compromising their structure!
how to make chewy monster cookies
1. Cream together butter and sugars.
2. Mix in peanut butter.
3. Whisk in remaining wet ingredients to combine.
4. Add in dry ingredients and mix until you have a thick cookie dough.
5. Fold in m&m's and chocolate chips.
6. Scoop 3 tablespoon sized portions of dough onto a baking sheet.
7. Bake until the cookies are spread out and golden brown along the edges. You can press some extra m&m's and chocolate chips on top of the warm cookies if you'd like - or just leave them as is.
8. Cool the cookies. Let the cookies sit for about 5 minutes on the baking sheet for them to firm up slightly, then transfer onto a wire rack to cool completely.
best peanut butter for monster cookies
Avoid natural peanut butter when baking (unless the recipe specifically calls for it) as it's much looser and less creamy than processed peanut butter. Natural peanut butter will cause your cookies to overspread and flatten when they bake.
The best peanut butter for baking is creamy peanut butter. Skippy or Jif are the most popular brands and my personal favorites, but you could use any brand you love as long as it's processed peanut butter.
how to get perfectly round cookies
This was a game changer for me when I first learned this trick! When the cookies first come out of the oven, they're going to look a little wonky and lopsided. You could for sure leave them as is (and it would add to the "monster" look!)
Buuuuut for perfectly smooth edges, here's the best trick: take a round cookie cutter that's slightly larger than your cookies and place it over a cookie fresh from the oven (while it's still soft and malleable!) Use the cookie cutter to push the rough edges in and shape into a perfectly round cookie!
Keep the monster cookies stored in an airtight container or plastic bag. These will keep for about 4 days at room temperature or 1 to 2 weeks in the fridge.
make ahead instructions
You can make the cookie dough up to 3 days in advance and keep it stored in the fridge until you're ready to scoop and bake the cookies.
You can also freeze cookie dough balls to keep a stash of cookies to bake off later on down the line! The best way to freeze cookie dough is to scoop portions of dough onto a parchment lined baking sheet and freeze until solid.
Once solid, take the frozen cookie dough portions and place them into a freezer bag in one layer. Push out as much air as you can and seal well. Freeze for up to 3 months. No need to thaw before baking - they'll just need an additional 2 minutes in the oven.
check out these other recipes!
Chewy Monster Cookies Recipe
- ½ cup (1 stick / 115g) unsalted butter, at room temperature
- ¾ cup (150g) packed brown sugar, light or dark
- ¼ cup (50g) granulated sugar
- ½ cup (120g) creamy peanut butter (not natural pb or the cookies will overspread)
- 1 large egg, at room temperature
- 2 tablespoons whole milk
- 1 teaspoon pure vanilla extract
- 1 & ¼ cups (150g) all-purpose flour, spoon and leveled
- 1 cup (80g) old-fashioned rolled oats
- 1 teaspoon baking powder
- 1 teaspoon baking soda
- ¼ teaspoon salt
- ¾ cup (150g) milk chocolate m&m's
- ½ cup (85g) semi-sweet chocolate chips or chunks
- Preheat your oven to 350°F. Line 2 large baking sheets with parchment paper, and set aside.
- In a large bowl, combine butter, brown sugar, and granulated sugar. Using an electric mixer fitted with the paddle attachment or a spatula by hand, cream together until lightened in color and fluffy. This'll take about 1 minute with a mixer set to medium high speed or 2 minutes by hand.½ cup (1 stick / 115g) unsalted butter,, ¾ cup (150g) packed brown sugar,, ¼ cup (50g) granulated sugar
- Add your peanut butter and mix to combine.½ cup (120g) creamy peanut butter
- Whisk in egg, milk, and vanilla. The mixture may look a little grainy, but that's totally fine!1 large egg,, 2 tablespoons whole milk, 1 teaspoon pure vanilla extract
- Add in your flour, oats, baking powder, baking soda, and salt. Fold together until you have a thick sticky dough.1 & ¼ cups (150g) all-purpose flour,, 1 cup (80g) old-fashioned rolled oats, 1 teaspoon baking powder, 1 teaspoon baking soda, ¼ teaspoon salt
- Fold in m&m's and chocolate chips to combine. The dough will be quite sticky so you'll need a cookie scoop to portion out the cookies. In a pinch, you could use 2 spoons, but the cookies won't be quite as even - still delicious though!¾ cup (150g) milk chocolate m&m's, ½ cup (85g) semi-sweet chocolate chips or chunks
- Use a large cookie scoop to portion out balls of cookie dough about 3 tablespoons in size. Drop the portions onto your parchment lined baking sheet, leaving about 2 inches of space between each cookie.
- Bake the cookies in the center of your preheated oven for 10 to 12 minutes, or until spread out and golden brown along the edges. While they're warm from the oven, sprinkle over more m&m's and chocolate chips if desired.
- Cool the cookies for 5 minutes on the baking sheet, then transfer onto a wire rack to cool completely before digging in!