Cornflake Crunchie Cookies (Extra Gooey)

by donuts2crumpets | Jan 19, 2026 | Cookies Bars & Brownies

There’s something magical about a cookie that feels both nostalgic and a little bit mischievous — and these Cornflake Crunchie Cookies are exactly that. They’re soft and chewy in the center, crisp around the edges, and packed with buttery malted cornflake clusters that stay crunchy even after baking. Add in melty mini marshmallows and a sprinkle of chocolate chips, and you’ve basically created the cookie version of every childhood cereal treat… but upgraded for grown‑ups who still love a cozy, sweet moment.

gooey cornflake crunchie cookies with marshmallows and chocolate chips

They’re fun, they’re messy in the best way, and they’re the kind of cookie that disappears from the cooling rack long before they make it to the cookie jar.

A couple of tips for Cornflake Crunchie Cookies:

Vegan marshmallows melt more slowly and hold their shape better, so they’re a great option if you want to just mix the marshmallows straight in to the cookies rather than stuff them. Trader joes has vegan marshmallows!
Don’t overmix once the crunchies go in. Overmixing breaks the clusters!
For thicker cookies, scoop and shape higher rather than wider. This will help your cookies stay thicker.

Ingredients:

Cornflake Crunchies:

2-1/2 cups cornflakes
1/4 cup malted milk powder
2 Tbsp granulated sugar
1/4 tsp salt
1/4 cup (1/2 stick) melted butter, salted

Cookie Dough:

1 cup (2 sticks) butter, room temp
1-1/4 cups granulated sugar
3/4 cup brown sugar, packed
1 egg plus an extra yolk
1 tsp vanilla extract or vanilla paste
2-1/4 cups AP flour
2 Tbsp cornstarch
1 tsp baking soda
1/2 tsp salt
2 cups Cornflake Crunchies (ingredients above)
1 cup mini chocolate chips
1-1/2 cup mini marshmallows, divided

Instructions:

Make the Cornflake Crunchies:

Preheat the oven to 275F and line a large baking sheet with parchment paper
In a mixing bowl, add the cornflakes and use your hands to crush them up a bit
Add the malted milk powder, sugar and melted butter, and toss well with a fork until completely combined
Spread the cornflake mixture on to your prepared baking sheet and bake at 275F for 20 minutes.
Remove the baking sheet from the oven and let them completely cool
Break in to bite size crunchies and store in an airtight container until ready to use.

Make the Cornflake Crunchie Cookies:

Preheat the oven to 375 and line two large baking sheets with parchment paper
In your stand mixer, cream the softened butter and both sugars together for 3 minutes
Add in the eggs and vanilla, then beat together for an additional 1-2 minutes
In a separate bowl, whisk together the flour, cornstarch, baking powder and salt
Add the flour mixture to the butter mixture and stir together on slow speed until combined
Add in the mini chocolate chips and 2 cups of the cornflake crunchies, then mix until just combined
Use a 3 Tbsp cookie scoop to grab a scoop of batter. Flatten it in your palm, and add 5-6 mini marshmallows to the center, then pull the flattened dough up to the top, making a ball, but letting the marshmallows peek out the top a little
Place on a prepared baking sheet and continue to make balls until your baking sheet is full, but leaving a couple of inches between each cookie
Freeze the tray for 10 minutes, then bake at 375 for 11-12 minutes or until starting to get golden brown
Remove from the oven and let the cookies cool completely on the tray
(While your first batch is baking, you can put your second batch together and freeze them)