Baking Recipes,  Cookies,  From the books

The well loved Cornflake Marshmallow Chocolate Chip Cookies from Milk Bar NYC

These addictive Cornflake Marshmallow Chocolate Chip Cookies are ooey gooey, crunchy, and chewy all at the same time. They’re also salty, chocolatey, with some toffee notes. I understand why they’re a bestseller at Momofuku Milk Bar!

I love Christina Tosi. She’s definitely one of the most creative pastry minds in the world at the moment. Sometimes I watch videos of her making things on YouTube when I need a little inspirational boost. Despite the fact that I didn’t get to visit any Momofuku Milk Bar shops while I was in New York– yes yes, I regret it immensely!– I admire her a lot.

I mean, probably every dessert aficionado does at this day and age. I particularly enjoy the things she does with cereal!

However I am pretty terrified of her recipes. Reading the reviews on her cookbooks has left me feeling so intimidated I haven’t bought any of them. Apparently her recipes are really finicky, and you have to follow them EXACTLY to the letter to succeed.

As we all know, there are times that recipes like that still fail even if you think you’ve followed to a T. There are other factors like differences in oven temperature, maybe even in the quality of ingredients. Or it could be a difference in the state of mind haha!

In all honesty, making this recipe was quite nerve-wracking for me. But I wanted to try it anyway, because I want a piece of Tossi’s magic in my kitchen. Of course, it would only be magic if I pulled the recipe off. I did some research and found that what most bloggers had issue with was the baking time of this cookie. There were some other bits too, so I soaked all of those things in when it was my turn to make this, and this is what happened.

Oh yes. These gooey crunchy yummy Cornflake Marshmallow Chocolate Chip Cookies are AS GOOD AS THEY LOOK.

Sometimes when you read about a recipe that has had people failing at it a lot, it can really sour your mood. So I have to give a special shoutout to Margaret in the City’s blog, where I found her Momofuku Milk Bar creations. She’s the one who really made me feel more and more emboldened until I simply didn’t want to put this recipe off any longer.

So now that I’ve tried it and realized it’s not actually as complicated as everybody seems to be letting on, I’m here with some important tips!

Recipe notes

There were a few things I discovered about this recipe that I feel like I need to share with you all, so let me give you a quick run through of the process. (And as always, the detailed instructions with my own recommendations are in the recipe box down below!)

First, DO NOT leave your cornflake crunch in the oven longer than necessary.

Before you start your cookie dough, you have to make the cornflake crunch first. This is one of those genius things Tosi has done with cereal, where you create these milky chunks of sweet rocks by mixing together crushed cornflakes, milk powder, sugar, salt, and melted butter.

It’s going to look like weird wet pieces of cereal when you spread it out onto the baking tray but don’t worry, it will come together in the oven.

I made the mistake of stepping away from the oven for a bit and did not hear it ring when the time was up. I managed to rush back, but as you can see I had mostly beyond golden, overcooked pieces of cornflake crunch. I did have to remove some burnt pieces, but thankfully I still had lots left over.

I just want to say, I’m glad I did not let this cornflake crunch blunder deter me from making the cookies a day later. These overcooked crunch bits turned into toffee inside my cookies. 😉

Second, DO NOT skip the 10-minute mixing period for the dough.

This recipe pretty much starts out the same as most other recipes. You’re going to cream your sugar and butter together for 2 to 3 minutes. Don’t forget to scrape down the side of your bowl.

And then you add your egg and vanilla.

The vanilla I used is the clear type, which is what I noticed Tosi prefers with most of her recipes. You can just use whatever vanilla extract you have on hand.

Here’s the part where you have to let your batter mix for another 7 to 8 minutes, so that it gets a total mixing time of 10 whole minutes. I highly recommend using the stand mixer here. 10 minutes is a LONG time to be mixing with your arm, or for holding the hand mixer for that matter.

After that mixing period, you’re going to get a batter that has lots of airy body and actually looks like swiss buttercream:

The batter is super fluffy because it’s been whipped so long and this is what you want to maintain in this batter. Which is why the next bit is also crucial…

Third, DO NOT overmix the dough once you’ve fluffed it up.

Now you’re going to add in your mixture of dry ingredients, turning your stand mixer to low and just letting the paddle run the flour into the batter for less than a minute.

Don’t worry about the flour streaks you see in the dough since you will still be mixing the batter one last time when you add the chocolate chips, mallows, and the prepared cornflake crunch.

We’re using the spatula for this part to avoid overmixing the dough. I like to mix the add-in’s while they’re in their own bowl before dumping it into the dough altogether. Then just fold them into the dough until they’re just well distributed, and no more. Do not keep mixing so that the dough stays soft and fluffy.

I know this looks more like thick batter than dough at this point, but you’ll find that it will be easy to scoop. I used an ice cream scoop but you can also use a 1/4 measuring cup to portion the dough onto your tray. You can put them close together (but not touching) at this point since we’ll pop them in the freezer. I like to press a few pieces more of mini chocolate chips and marshmallows on top for good measure.

Fourth, DO NOT forget to refrigerate or freeze the dough. And please DO keep the unbaked batches of dough inside the fridge or freezer!

Once the mounds are ready, cover with cling wrap and freeze for 30 minutes, or refrigerate at least 1 hour or up to 1 week. Being as impatient as I am, I froze them so I can bake them asap. I baked just four mounds at a time using my smaller baking trays since these cookies do spread! But because I froze them, they baked perfectly at 375°F (190°C) for 15 minutes.

Some people were saying that the temperature was a bit too much for their cookies, so if you’re baking from the refrigerator, I suggest turning your oven down to 350°F (180°C) instead. Just to be on the safe side! Watch the cookies around the 10 minute mark as well if they look ready.

Fourth, DO NOT move the cookies while they are fresh out of the oven. They will harden as they cool.

Chocolate Chip Cookies are normally soft out of the oven so as a general rule, moving them isn’t the best thing to do. But since these cookies are very thin things to boot, I really do not recommend moving them at all. None of my cookies turned into puddles thankfully, but they’re perhaps the thinnest chocolate chip cookies I’ve ever encountered.

I’m glad I decided to add more choco chips and marshmallows on top of the cookie mounds because now they look like something you eat at a campfire! Those toasted bits of marshmallow that make these sticky webs when you break the cookie in half is part of the experience of eating these Cornflake Marshmallow Chocolate Chip Cookies!

As for the taste, these are honestly one of my favourite variations of the chocolate chip cookie. So cleverly done! It’s got the usual notes of chocolate and caramel but brought to a next level. The marshmallows add a gooey delightful sweetness, and the cornflake crunch is like toffee inside the cookies I tell ya! One bite is all it takes to understand the hype!

Milk Bar's Cornflake Marshmallow Chocolate Chip Cookies

These addictive cookies are ooey gooey, crunchy, and chewy all at the same time. They're also salty, chocolatey, with some toffee notes. I understand why they're a bestseller at Momofuku Milk Bar!

Makes 12 to 16 cookies


For the Cornflake Crunch

  • 170 grams cornflakes cereal
  • ½ cup milk powder
  • 3 tablespoons white sugar
  • 1 teaspoon kosher salt
  • 9 tablespoons unsalted butter, melted

For the Cookies

  • 1 cup unsalted butter, room temperature
  • cups white sugar
  • cup tightly packed brown sugar
  • 1 egg
  • ½ teaspoon vanilla
  • cups all-purpose flour
  • ½ teaspoon baking powder
  • ¼ teaspoon baking soda
  • teaspoons kosher salt
  • 3 cups Cornflake Crunch, from above
  • cup mini chocolate chips, plus more for topping
  • cups mini marshmallows, plus more for topping


To make the Cornflake Crunch

  • 1. Preheat oven to 275°F (135°C). Line a baking tray with parchment paper.
  • 2. Into a medium bowl, pour cornflakes and crush with your hands until they are 1/4 of their original size. Add in the powdered milk, sugar, and salt. Mix together.
  • 3. Drizzle in the melted butter and mix until completely coated and combined. Spread cornflakes into a thin layer on the prepared baking sheet. Bake for 15 to 20 minutes until dry and crispy. Cool completely before incorporating into your cookies or storing in an airtight container.

To make the cookies

  • 4. In the bowl of a stand mixer using the paddle attachment, cream butter, brown sugar, and white sugar together on medium-high for 2 to 3 minutes. Scrape down the sides of the bowl.
  • 5. With the mixer on low, add in egg and vanilla. Beat for another 7 to 8 minutes on medium-high, until batter is light and fluffy, almost like frosting. Do not skip this step!
  • 6. Meanwhile, whisk together flour, baking powder, baking soda and salt in a small bowl. Once the butter-sugar mixture is ready, reduce mixer speed to low and gradually add in the flour mixture (so that the flour doesn't fly everywhere). Mix until just combined, not over 1 minute. Do not over mix!
  • 7. Using a spatula, mix in mini chocolate chips, Cornflake Crunch, and marshmallows, until just incorporated. Again, do not over mix! The dough will be very soft.
  • 8. Using a cookie/ice cream scoop or your 1/4 measuring cup, portion out mounds of dough onto a parchment-lined baking sheet. You can position them close together at this point, but not too close that they will stick against each other. Press down the tops of each cookie mound to flatten them slightly, then gently press a few pieces of marshmallows and mini chocolate chips on top. (Do not press them all the way in. The cookies will look better this way once baked.)
  • 9. Cover the prepared cookie dough with cling wrap and freeze for 30 minutes, or refrigerate at least 1 hour (up to 1 week).
  • 10. Once ready to bake, preheat your oven to 375°F (190°C) about 30 minutes before baking. Line three baking sheets with parchment paper.
  • 11. Take out the tray of frozen cookie dough from the freezer and place the first few pieces of frozen/chilled cookie dough 4 inches apart on the prepared baking sheet. Bake only four to five cookies at a time depending on the size of your baking sheet since these spread out quite a bit. While the first batch of cookies are baking, return the rest of the mounds back into the freezer/fridge. (Do NOT bake your cookies from room temperature as they will not hold their shape and bake into a puddle instead.)
  • 12. Bake one tray at a time in preheated oven, anywhere between 8 to 15 minutes*, until the edges become golden brown and cookies are just beginning to brown toward the centre. Keep an eye on the cookies to prevent from overbaking, since ovens vary. I baked mine for about 15 minutes. Continue with the rest of the cookies. Use cool lined baking sheets for each batch, and keep in mind to return the cookie dough into the freezer or fridge when it's not their turn to bake yet.
  • 13. Cookies will be soft fresh out of the oven. Cool cookies completely on the sheet pans before moving or transferring to an air tight container. They will be a little thinner than the usual chocolate chip cookies. These cookies will keep fresh for 5 days at room temperature in an air tight container.


Some people suggest baking at 350°F (180°C) because the cookies end up spreading too much at 375°F (190°C), but when I tried the lower temperature using cookie dough from the FREEZER, I had to bake it for a little over 20 minutes before they were ready. Use this temperature if baking with refrigerated dough. If the dough is frozen, the higher temperature should be perfect.
Adapted from <a href=""><i>Momofuku Milk Bar</i> by Christina Tosi</a>, via various sources on the web

In all honesty, I got inspired in part to make these Cornflake Marshmallow Chocolate Chip Cookies as I was writing my way through my New York travel diaries. The regret didn’t fully hit until I got to the last one, where I had to relive my tiny tiny Brooklyn experience. I literally just brushed against the surface of what Brooklyn had to offer, so I really have to make up for that when I return.

If you want to check out my New York Travel Diaries 2016 edition, here’s the full set of them. Links are on the captions that pop out when you hover over the pictures. 🙂

Tips for New York City
12 Tips for your first time in NYC!


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