If you’ve never thought to put cereal or marshmallows into cookies, you may wish to rethink that.

Cornflake Chocolate Chip Marshmallow Cookies

I’ve made plenty of Rice Krispies Bars and Chocolate Candy Cereal Bars with with cereal and marshmallows, but have never put them into cookies.

Why not? I have no idea. But there was no time like the present to start.

Cornflake Chocolate Chip Marshmallow Cookies

Here are my candid thoughts and notes about the cookies and recipe, which is from Christina Tosi’s Momofuku Milk Bar Cookbook. I am posting it as part of the Milk Bar Mondays group I’m part of and a half dozen of us all made this recipe this week. Unfortunately, many of had some baking fails, ranging from mild to severe.

I wrote Tosi’s recipe (below) as it is written in her book. However, I halved the recipe because I didn’t need 15 to 20 large bakery style cookies just layin’ around. I yielded 9 large cookies, which was plenty. These things are about the size of soccer balls.

Cornflake Chocolate Chip Marshmallow Cookies

I followed her recipe to the T. I never follow recipes exactly, but I did in this case because I know what a stickler she is for directions and implies that if you don’t follow her recipes exactly, there’s no telling if it will work or not.

As long as I was going to put the time and energy into making these cookies, and all that butter and sugar too, I wanted the recipe to work.

I didn’t use measuring cups and exclusively used my food scale, weighing each and every ingredient down to the gram. It was literally an exact science.

Cornflake Chocolate Chip Marshmallow Cookies

You must chill the dough for at least one hour, or up to one week. I chilled my dough for approximately 44 hours. Almost two days.

I slightly patted down the domed tops of my cookie dough balls before chilling them, but didn’t make them as flat as hockey pucks which was a good call as these cookies needed all the help they could get in terms of staying puffy. They spread and flattened, dramatically. This was very disappointing as I watched them splooge and spread while they were baking. I wanted to beat on the door of my oven and scream, No, Don’t You Dare Spread! But they did anyway.

Cornflake Chocolate Chip Marshmallow Cookies

She suggests baking these cookies for 18 minutes, but when I made Compost Cookies using her recipe, I thought those cookies were on the cusp of being too overdone for my liking and she suggests a similar baking time in that recipe.

With that knowledge, I decided to start watching these cookies closely at about 13 minutes and I’m glad I did. My cookies were done and crispy at 13 1/2 to 14 minutes and at 18 minutes I would have had set off the smoke alarm. Butter burns in a hurry.

I love the addition of the Cornflake Crunch (you make a batch of that before you actually make the cookies) but don’t feel it’s worth the extra step. I will use crushed Frosted Flakes straight from the box next time if I feel the need for flaky sweet cereal in cookies.

I thought the cereal and marshmallows were great in combination, especially with the chocolate chips (I used regular-sized chocolate chips, not mini). Sort of like having smores within cookies. Look at those toasty marshmallows. A perfect gooeyfest.

Cornflake Chocolate Chip Marshmallow Cookies

The dough, like all her doughs, is heavy on the butter. The cookies are very buttery and rich, but I couldn’t get over their lack of puffiness.

A puffy, chewy cookie, with less crispiness and more softness is as important to me as taste and these weren’t as puffy or soft ‘n chewy as I had hoped.

And I honestly have no idea what I could have done differently. It’s interesting because when I googled this recipe, every blog post I came across for these cookies shows paper thin cookies that are of the less-than-perfectly-photogenic variety so I know I am not alone.

Cornflake Chocolate Chip Marshmallow Cookies

I researched online to find out the causes of flat or spreading cookies and the general issues contributing to the problem include:

dough too warm (mine was chilled for two days, not my problem)

high butter content cookies spread more easily (yes, that’s these)

large cookies don’t have as good of a chance at puffing compared to smaller cookies because of their sheer mass and size (check again, these are cookies are little bowling balls at 1/3 cup of raw dough, each)

Cornflake Chocolate Chip Marshmallow Cookies batter

Overall, I loved the combination of crunchy cereal that stayed fairly crunchy, the gooey melty marshmallows, and it’s fun to try new cookie recipes.

However, I have my go-to chocolate chip cookie recipe (that rolls chocolate chip, subtle peanut butter, and oatmeal cookies all into one) and will probably add some fun add-in’s like cereal or marshmallows to that dough base in the future because I know it gives me the puff and chewiness I want. Not that these were awful or anything.

Cornflake Chocolate Chip Marshmallow Cookies

Cornflake Chocolate Chip Marshmallow Cookies

Cornflake-Chocolate-Chip-Marshmallow Cookies
Yield: 16

Cornflake-Chocolate-Chip-Marshmallow Cookies

Prep Time 30 minutes
Cook Time 40 minutes
Total Time 1 hour 10 minutes

Smores-inspired cookies the size of your head with crunchy Cornflake clusters baked in! It’s the famous Momofuku Milkbar recipe and so good. Make sure to read over the blog post for tips and tricks to ensure cookie success.



  • 225 g butter, room temperature (16 tablespoons, 2 sticks)

  • 250 g granulated sugar (1 1/4 cups)
  • 150 g light brown sugar (2/3 cup tightly packed)
  • 1 egg
  • 2 g vanilla extract (1/2 teaspoon)
  • 240 g flour (1 1/2 cups)
  • 2 g baking powder (1/2 teaspoon)
  • 1.5 g baking soda (1/2 teaspoon)
  • 5 g kosher salt (1 1/4 teaspoons)
  • 3/4 recipe Cornflake Crunch which is 270 g (3 cups), see below
  • 125 g mini chocolate chips (2/3 cup)
  • 65 g mini marshmallows (1 1/4 cups)

Cornflake Crunch

  • 170 g cornflakes (haf of 12-ounce box, 5 cups)
  • 40 g milk powder (1/2 cup)
  • 40 g sugar (3 tablespoons)
  • 4 g kosher salt (1 teaspoon)
  • 130 g butter, melted (9 tablespoons)


Cornflake Crunch

  1. Heat oven to 275F. Pour the cornflakes in a medium bowl and crush them with your hands to one-quarter of their original size. Add milk powder, sugar, salt, and toss to mix. Add butter and toss to coat; butter will act as the glue binding the dry ingredients to the cereal creating small clusters.
  2. Spread the clusters on a parchment- or Silpat-lined sheet pan and bake for 20 minutes, at which point they should look toasted, smell buttery, and crunch gently when slightly cooled and chewed. Cool the cornflake crunch completely before storing or using in a recipe. Stored in an airtight container at room temperature, the crunch will keep fresh for 1 week; in the fridge or freezer, it wil keep for 1 month.

Making the Cookies

  1. Combine the butter and sugars in the bowl of a stand mixer fitted with the paddle attachment and cream together on medium-high for 2 to 3 minutes. Scrape down sides of bowl, add the egg and vanilla, and beat for 7 to 8 minutes.
  2. Reduce the mixer speed to low and add the flour, baking powder, baking soda, and salt. Mix just until the dough comes together, no longer than 1 minute (do not walk away from mixer or overmix). Scrape down sides of bowl.
  3. Still on low speed, paddle in the cornflake crunch and chocolate chips until just incorporated, no more than 30 to 45 seconds. Paddle in marshmallows until just incorporated.
  4. Using a 2 3/4-ounce ice cream scoop or a 1/3 cup measure, portion out the dough onto a parchment-lined sheet pan. Pat the tops of the dough domes flat. Wrap sheet pan tightly in plastic wrap and refrigerate for at least 1 hour, or up to 1 week. Do not bake your cookies at room temperature – they will not hold their shape.
  5. Heat oven to 375F. Arrange the chilled dough a minimum of 4 inches apart on parchment- or Silpat-lined sheet pans. Bake for 18 minutes. The cookies will puff, crackle, and spread, At the 18-minute mark, the cookies should be browned on the edges and just beginning to brown toward the enter. Leave them in the oven for an additional minute or so if they aren’t and still seem pale and doughy on the surface.
  6. Cool the cookies completely on the sheet pans before transferring to an airtight container for storage. At room temperature, the cookies will keep fresh for 5 days; in the freezer, they will keep for 1 month.


Recipe from Christina Tosi’s Momofuku Milk Bar Cookbook

Nutrition Information:



Serving Size:


Amount Per Serving: Calories: 414Total Fat: 21gSaturated Fat: 13gTrans Fat: 1gUnsaturated Fat: 6gCholesterol: 60mgSodium: 490mgCarbohydrates: 56gFiber: 1gSugar: 35gProtein: 3g

Other Momofuku Milk Bar Cookbook-Inspired Recipes

Cinnamon Bun Pie – I made a 10 minute cheater’s version and highly recommend it. Best way to doctor up a can of cinnamon rolls, ever.

Cinnamon Bun Pie

Crack Pie –  as addictive, decadent and fabulous as the name sounds. Labor-intensive, but worth it.

"crack pie" sugary pie filling

Buttery Toasted Cap’n Crunchies – I used her Cornflake Crunch idea as inspiration and the result is buttery, toasted cereal that tastes like one big bowl of buttered toast pieces. If you like buttered toast, this is your recipe. I prefer Cap’n Crunchies to the Cornflake Crunch as I think these have more flavor and more texture.

Buttery Toasted Cap'n Crunchies

Compost Cookies – Potato chips in cookies, with the salty ‘n sweet combination, really is so good. Don’t knock it til you try it.

Potato chip cookies

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