Cornflake Marshmallow Cookies

makes 12-15 cookies
recipe adapted from Momofuku Milk Bar

  • 1 cup (2 sticks) unsalted butter, room temperature
  • 1 cup granulated sugar
  • 2/3 cup packed light-brown sugar
  • 1 large egg
  • 1/2 teaspoon pure vanilla extract
  • 1  1/2 cups all-purpose flour
  • 1  1/4 teaspoons coarse salt
  • 1/2 teaspoon baking powder
  • 1/4 teaspoon baking soda
  • 3 cups cornflakes
  • 1/3 cup mini chocolate chips (I cut up a Hershey’s bar!)
  • 1/3 cup peanut butter chips
  • 1  1/4 cups mini marshmallows

Cream together butter and both sugars in the bowl of an electric mixer fitted with the paddle attachment on medium-high, 2 to 3 minutes. Scrape down sides of bowl and add egg and vanilla; beat for 4 to 5 minutes.

Reduce speed to low and add flour, salt, baking powder, and baking soda. Mix just until dough comes together, no longer than 1 minute. Scrape down sides of bowl with a spatula.

With the mixer on low, add cornflake crunch and both chocolate & peanut butter chips; mix until just combined, 30 to 45 seconds. Add mini marshmallows and mix until just incorporated.

Line a baking sheet with parchment paper. Using a 2 3/4-ounce ice-cream scoop or 1/3-cup measuring cup, portion dough out onto prepared baking sheet. Pat tops of cookie domes flat. Wrap baking sheet tightly with plastic wrap and refrigerate for at least 1 hour and up to 1 week. Do not bake cookies from room temperature or they will not hold their shape.

Preheat oven to 375 degrees. Line additional baking sheets with parchment paper or nonstick baking mats.

Arrange chilled dough at least 4 inches apart on prepared baking sheets. Transfer to oven and bake until puffed, cracked, spread, and browned on the edges, about 12-15 minutes. Let cool completely on baking sheets.


The cookies have a high butter to flour ratio, which is why a chill in the fridge is necessary. I suggest chilling for at least 3 hours. If you want, you can freeze the cookies and bake them off. They work out perfectly- you might need to adjust baking time by a few minutes. Also in my research of the cookie, I read that the original 18 minutes the cookie was to bake for produced a burnt cookie so in my oven 12-15 was the right zone. Keep an eye on your cookies before they get too dark. You want them crisp around the edges. They harden as they cool.