
If you’ve ever wandered through Costco, and tried one of their delicious crispy marshmallow cookies, and thought “Hmmm I wonder if I could make these at home…”—you’re in the right place. These Brown Butter Crispy Marshmallow Cookies are a homemade love letter to that iconic chewy-crisp texture, with even more flavor thanks to golden brown butter, toasted marshmallows, and crunchy pockets of Rice Krispies. They are better than the ones you can buy, trust me. Honestly, most things are better homemade, in my opinion!

They’re packed with flavor. They’re gooey. They’re crunchy. They’re AMAZING.
Why You’ll Love These Crispy Marshmallow Cookies (like Costco)
✨ Brown butter = next-level flavor
Toasting the butter gives these cookies the deepest caramelized, nutty flavor—like your favorite chocolate chip cookie went gourmet.
✨ Chewy + crispy texture
The Rice Krispie cereal adds crunch while the marshmallows melt into pockets of gooey goodness.
✨ Costco copycat…but better
You get the same vibes, but you control the sweetness, the texture, and the size. (Though I fully support making them giant.)
✨ Failsafe dough
This dough requires no chilling and bakes beautifully every time.

And the best part? They come together with simple pantry ingredients and zero fuss. You could easily add some get a green sprinkles to make them the perfect treat for Christmas!
Tips for the Best Copycat Cookies
💡 Let the brown butter cool slightly before mixing so it doesn’t melt the sugar too much.
💡 Don’t overbake! These cookies should stay soft in the middle.
💡 Press extra marshmallows on top for that bakery-style toasted look.
💡 Size them big if you want that true Costco vibe—¼ cup scoops work great. Here is the regular size cookie scoop

Other Favorite Christmas Cookies
- The BEST Gingersnaps
- Swig Peppermint
- Roll Out Sugar Cookies
- Sugar Cookie Bars
- Hot Chocolate Cookies
- Eggnog Thumbprints
Crispy Marshmallow Cookies (like Costco)
Description
These Brown Butter Crispy Marshmallow Cookies capture everything we love about the Costco version—chewy, rich, gooey, crispy edges—but even better and from your own kitchen.
Ingredients
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1 cup salted butter
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1 1/4 cup brown sugar
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3/4 cup granulated sugar
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2 large egg, room temperature
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2 teaspoon vanilla (vanilla paste is AMAZING here)
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1 teaspoon baking soda
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3/4 teaspoon salt
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2 cup all-purpose flour
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3 cups Rice Krispie cereal
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1 1/3 cup (heaping cup) mini marshmallows
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Flaked sea salt for topping (if desired)
Instructions
Add your butter to a small saucepan and melt it over medium heat. Keep cooking, swirling occasionally, until it turns golden brown and smells nutty and caramel-like. Remove from heat and let it cool (place in freezer for 8-10 min).
In a mixing bowl, stir together the brown sugar, granulated sugar, and brown butter. Mix until smooth and glossy.
Beat in the egg and vanilla extract (or paste!) until fully combined.
Sprinkle in the flour, baking soda, and salt. Mix just until the dough comes together—don’t overdo it.
Gently stir in the Rice Krispies and mini marshmallows. It’s okay if some marshmallows peek out—those caramelize beautifully in the oven. The dough will be pretty stiff.
Scoop the dough onto a parchment-lined baking sheet. Press a few extra marshmallows on top (optional but highly recommended!) and sprinkle lightly with flaked salt.
Bake at 350°F (175°C) for 9–11 minutes, or until the edges are lightly golden and the centers look just set. Let them cool on the pan to finish firming up.
Notes
Storage
These cookies stay soft for 3–4 days in an airtight container…but good luck not eating them all in 24 hours. They also freeze beautifully (both baked and unbaked!).

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