Introduction

These Marshmallow Crispy Cookies are a delightful Costco copycat treat combining the chewiness of marshmallows with crispy rice cereal in a perfectly browned butter cookie. They’re easy to make and deliver a wonderful balance of textures and flavors that everyone will love.

The image shows three round oatmeal cookies on a white parchment paper placed on a rusty, dark metal baking tray. Each cookie has a golden-brown color with a slightly rough and crumbly texture. In the center of each cookie, there are visible toasted marshmallows, white with golden-brown spots, blending into the oat base. Small flakes of sea salt are scattered on the surface of the cookies, adding a slight shine. The tray sits on a white marbled surface. photo taken with an iphone --ar 4:5 --v 7

Ingredients

½ cup salted butter
¾ cup brown sugar
½ cup granulated sugar
1 large egg (room temperature)
1 teaspoon vanilla (vanilla paste recommended if available)
½ teaspoon baking soda
¾ teaspoon salt
1 cup + 2 tablespoons all-purpose flour
1½ cups rice krispie cereal
⅔ cup mini marshmallows
Flaked salt for topping

Instructions

Step 1: Preheat the oven to 350°F (175°C). Line a baking sheet with parchment paper.
Step 2: Brown the butter by melting ½ cup salted butter in a medium saucepan over medium heat. Continue cooking past the boiling point while stirring constantly. Watch closely for the butter to turn golden brown and develop a nutty aroma, then immediately remove from heat.
Step 3: Pour the browned butter into a bowl and chill in the fridge or freezer for about 10 minutes until cool.
Step 4: In a mixing bowl, combine the cooled browned butter with the brown sugar and granulated sugar. Mix on low speed until smooth, about 30 seconds.
Step 5: Add the egg and vanilla to the bowl, and mix gently on low until combined.
Step 6: Slowly incorporate the salt, baking soda, and flour into the wet ingredients, being careful not to overmix.
Step 7: Gently fold in the rice krispie cereal followed by the mini marshmallows.
Step 8: Using a 3-tablespoon cookie scoop, portion the dough into large balls. Place 4 to 5 cookies on each lined baking sheet, spacing them well as they spread thin.
Step 9: Bake for 10-13 minutes until the edges are lightly golden. Avoid overbaking to maintain a chewy center.
Step 10: Remove from oven and immediately sprinkle with flaked salt while the cookies are still warm.
Step 11: Allow cookies to cool on the baking sheet for a few minutes before transferring to a wire rack to cool completely.

Tips & Variations

Use vanilla paste instead of extract for a richer vanilla flavor.
Chill the dough for 15 minutes before scooping to help cookies hold their shape.
Substitute salted butter with unsalted butter plus a pinch of extra salt if preferred.
Add a handful of chopped nuts or chocolate chips for extra texture.

Storage

Store cookies in an airtight container at room temperature for up to 5 days. To keep marshmallows soft, add a slice of bread to the container. Reheat cookies briefly in the microwave for a warm, gooey treat.

How to Serve

A golden-brown cookie broken in half lying on a white marbled surface, revealing gooey melted marshmallow inside stretching between the two pieces; the cookie has a slightly crinkled texture with a few shiny salt flakes on top that add contrast to the soft, chewy center. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use regular marshmallows instead of mini marshmallows?

Yes, you can chop regular marshmallows into smaller pieces and fold them into the dough if mini marshmallows aren’t available.

Why is browning the butter important?

Browned butter adds a deep, nutty flavor and richness to the cookies that plain melted butter cannot provide, enhancing their overall taste.