Dessert

Brown Butter Marshmallow Crispy Cookies Recipe

ByMarina Montclair April 4, 2026April 4, 2026

Introduction

These brown butter marshmallow crispy cookies are a delightful twist on the classic rice krispie treat, baked into a thin, crispy, and chewy cookie. Loaded with crunchy rice krispies and gooey mini marshmallows, the caramel-flavored brown butter dough takes them over the top. They’re simple to make with no chilling required and taste even better than Costco’s version!

The image shows a close-up of four oatmeal cookies on a baking tray lined with white parchment paper, resting on a white marbled surface. Each cookie is round and golden brown with a slightly textured surface of oats and bits of marshmallow that have melted and browned in the center, giving a soft, shiny look. The edges are crisp and slightly darker, while the middle has a mix of light tan and golden colors with small salt flakes sprinkled on top. The baking tray is dark and worn with a rustic look, showing scratches and marks. photo taken with an iphone --ar 4:5 --v 7

Ingredients

½ cup (113.5 g) salted butter
¾ cup (165 g) brown sugar
½ cup (100 g) granulated sugar
1 large egg, room temperature
1 teaspoon vanilla (vanilla paste works great)
½ teaspoon baking soda
¾ teaspoon salt
1 cup (158 g) + 2 tablespoons all-purpose flour
1½ cups (43 g) rice krispie cereal
⅔ cup (30 g) mini marshmallows
Flaked salt for topping

Instructions

Step 1: Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper. Melt ½ cup of salted butter in a medium saucepan over medium heat, continuing to cook past the boiling point. Stir constantly as the butter foams and then turns golden brown with a nutty aroma. Watch carefully to avoid burning. Pour the browned butter into a bowl and chill in the fridge or freezer for about 10 minutes until cooled.
Step 2: In a medium mixing bowl, combine the cooled brown butter with brown sugar and granulated sugar. Add the egg and vanilla, mixing on low speed until smooth, about 30 seconds.
Step 3: Gradually add the salt, baking soda, and flour to the wet ingredients. Mix gently just until combined, being careful not to overmix the dough.
Step 4: Fold in the rice krispie cereal followed by the mini marshmallows to evenly distribute them through the dough.
Step 5: Using a 3-tablespoon cookie scoop or a spoon, portion the dough into large balls. Place 4-5 cookies per prepared baking sheet, spacing them well as they spread thin during baking.
Step 6: Bake for 10-13 minutes until the edges turn a light golden brown. Avoid overbaking to keep the centers chewy. Immediately after baking, sprinkle the cookies with flaked salt for a delicious contrast.

Tips & Variations

If the marshmallows spread and cause misshapen cookies, gently push the edges with a spatula or spoon to create a round shape before baking finishes.
For thicker cookies, add 2-3 tablespoons more flour to the dough.
Keep a close eye when browning butter as it can quickly go from perfect to burnt.
If you don’t have a kitchen scale, spoon flour lightly into measuring cups to avoid packing and keep cookies tender.

Storage

Store the baked cookies in an airtight container at room temperature for 2-3 days for the best freshness. You can prepare the cookie dough ahead and keep it chilled in the fridge for up to a week. For longer storage, freeze baked cookies in an airtight container for 2-3 months. Cookie dough balls can also be frozen and baked one at a time; if baking from frozen, reduce oven temperature to 325°F.

How to Serve

The image shows three round oatmeal cookies on white parchment paper on a dark, worn baking tray with a rustic look. Each cookie has one main layer, with a golden-brown color and a rough texture from the oats. Some white melted marshmallow pieces are visible in the center of each cookie, creating a soft, slightly shiny contrast. Tiny bits of coarse salt sprinkle on top, adding visual interest. The background beneath the tray is a white marbled texture. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use unsalted butter instead of salted butter?

Yes, you can use unsalted butter but be sure to add a pinch more salt to the dough to maintain flavor balance.

Will these cookies be very soft or crunchy?

These cookies are thin with a crispy edge and a chewy center thanks to the brown butter and marshmallows. They offer a nice balance of textures rather than being overly soft or dry.