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Cornflake Crunch Marshmallow Bars

Childhood foods elevated to the next level.

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Nothing encapsulates the feeling of childhood like the gooey, sticky, and sugary mess of marshmallows. Set ablaze over a campfire on a firefly-filled summer evening and melting into a cup of cocoa after a wintery day of sledding, marshmallows are a garnish that takes center stage. And while we may have grown up, that doesn’t mean our love of marshmallows has to fade. Enter these Cornflake Crunch Marshmallow Bars which are an updated way to get your daily dose of your past.

As we become adults, I think many people’s taste buds graduate from the pure injections of sugary food and opt for more balanced and subtle flavors. Yet there are still ways to enjoy our childhood favorites. This cookie bar does just that. Here, we take simple marshmallows and swaddle them with a bunch of complex textures. A chewy cookie base is laced with sweet-salty cornflake crunch. Loads of milk chocolate get added to the mix, and as the cookie bar bakes, this chocolate mixes with marshmallows to create a creamy and gooey molten delight.

To start this recipe off, we have to make the crumble. After crunching up a few cups of cornflakes in a bowl, mix in skim milk powder, sugar, and salt. Pour in the melted butter and toss until the mixture starts to clump. You spread it out onto a parchment-lined baking sheet and cook at a low temperature until nice and crisped. Once it cools down you can break it apart into smaller clumps. This crunch is dangerous, you may find yourself sneaking in a few bites!

Now comes the cookie base. Butter, granulated sugar, and light brown sugar get mixed in a bowl, followed by eggs and vanilla. A slow attrition of dry ingredients gets mixed in.

Next, you fold in the cooled cornflake crunch.

The marshmallows may bubble up and out of the pan, so place the baking pan on a cookie sheet while baking in the oven.

Here, I went about layering the cookie bar by spreading half of the dough into the bottom of a line and a greased pan.

Next, I added the chocolate and marshmallows and then covered everything with the remaining dough. If you don’t want to do this step, you can easily just mix the chocolate and marshmallows into the cookie dough and plop it right into the pans, no arts and craft layering is needed.

Once you bite into a square of these bars, you’ll be wondering why this isn’t more popular.

The marshmallows meld with the chocolate creating some amazing chocolate marshmallow fluff action. The cornflake crunch cuts through the soft, chewy textures giving a much-needed salty-crunchy contrast.

Give marshmallows a second chance in adulthood, these bars are so versatile that they can be made for a summer grill party, a September bake sale rush, and chowed down during the Christmas cookie exchange season, the reasons (excuses) to make these Cornflake Crunch Marshmallow Bars are endless!

Serves 12

20m prep time

30m cook time

Rated 5.0 out of 5
Rated by 5 reviewers
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you're making mealtime meaningful.
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For the Cornflake Crunch:
  • 4 cups cornflakes, roughly crushed
  • 1/3 cup powdered milk
  • 2 tablespoons granulated sugar
  • 1 teaspoon fine salt
  • 1/2 cup unsalted butter, melted
For the Cornflake Crunch Marshmallow Bars:
  • 2 1/2 cups all-purpose flour
  • 1 teaspoon fine salt
  • 1/2 teaspoon baking powder
  • 1/2 teaspoon baking soda
  • 1 cup unsalted butter, softened
  • 1 1/4 cups granulated sugar
  • 2/3 cup packed light brown sugar
  • 1 large egg, room temperature
  • 3/4 teaspoon vanilla extract
  • 2 cups marshmallows, either mini or cut-up large marshmallows
  • 8 ounces chocolate chips
To make the Crunch:
  1. Preheat oven to 275°F and line a baking sheet with parchment paper.
  2. In a large bowl mix together the crushed cornflakes, powdered milk, granulated sugar, and salt.
  3. Pour in the melted butter, tossing to combine, forming small clusters.
  4. Spread evenly onto a baking sheet and cook until the cereal is slightly toasted, about 15 to 20 minutes.
  5. Cool completely and then break up into large clusters.
To make the Cornflake Crunch Bars:
  1. Preheat oven to 350°F, line a 8x8 baking pan with parchment paper and grease with butter, and set aside.
  2. In a large bowl, whisk flour, salt, baking powder, and baking soda, set aside.
  3. With a mixer cream butter, granulated sugar, and light brown sugar until light and fluffy, about 3 minutes on medium speed.
  4. Add egg and vanilla and continue to beat for 8 minutes. This will aerate the batter.
  5. Lower the speed of the mixer and slowly add dry ingredients, mixing until just incorporated.
  6. Use a rubber spatula to gently fold in the cooled crunch-mixture.
  7. Divide the dough in half. Press one half into the prepared pan.
  8. Cover with chocolate and marshmallows.
  9. Top with remaining dough, pressing into an even layer and to the edges of the pan.
  10. Bake until golden brown, about 25 to 30 minutes.
  11. Let the bars cool completely before slicing and serving.

Recipe adapted from I Am Baker