Description
These Marshmallow Crispy Cookies are a delightful Costco copycat recipe featuring a thin, buttery cookie base with crispy rice cereal and mini marshmallows, topped with a sprinkle of flaky salt. The cookies have a chewy center and a nutty brown butter flavor that makes them irresistible.
Ingredients
Units
Scale
Wet Ingredients
- 1/2 cup (113.5 g) salted butter
- 3/4 cup (165 g) brown sugar
- 1/2 cup (100 g) granulated sugar
- 1 large egg room temperature
- 1 teaspoon vanilla paste or extract
Dry Ingredients
- 1/2 teaspoon baking soda
- 3/4 teaspoon salt
- 1 cup (158 g) + 2 tablespoon all-purpose flour
Add-ins and Toppings
- 1 1/2 cups (43 g) rice krispie cereal
- 2/3 cup (30 g) mini marshmallows
- Flaked salt for topping
Instructions
- Preheat Oven: Preheat your oven to 350°F and line a baking sheet with parchment paper for baking the cookies.
- Brown the Butter: Melt ½ cup of salted butter in a medium saucepan over medium heat. Continue cooking past the boiling point while stirring constantly until the butter turns a golden brown color and releases a nutty aroma. Watch carefully to avoid burning. Once browned, pour the butter into a separate bowl and chill in the fridge or freezer for about 10 minutes to cool.
- Mix Sugars and Butter: In a medium mixing bowl, combine the cooled brown butter with both the brown sugar and granulated sugar. Stir well to combine.
- Add Egg and Vanilla: Add the room temperature egg and vanilla paste (or extract) to the butter and sugar mixture. Mix on low speed until smooth, about 30 seconds.
- Add Dry Ingredients: Slowly incorporate the salt, baking soda, and flour into the wet mixture. Be careful not to overmix the dough to maintain tenderness.
- Fold in Cereal and Marshmallows: Gently fold the rice krispie cereal into the dough, followed by the mini marshmallows, ensuring even distribution.
- Form Cookies: Using a 3-tablespoon cookie scoop or large spoon, scoop dough into large balls. Place 4-5 cookies per lined baking sheet, spacing them well as they will spread thinly during baking.
- Bake: Bake the cookies for 11 minutes until the edges turn light golden brown. Avoid overbaking to keep the chewy center intact.
- Add Topping: Remove cookies from the oven and immediately sprinkle with flaked salt while still warm.
Notes
- For thicker cookies, add an extra 2 tablespoons of all-purpose flour to the dough.
- Using grams for flour measurement is more precise; if using cups, spoon the flour lightly into the measuring cup to avoid packing it down for best results.
- Brown butter adds a nutty richness—don’t rush this step to get the best flavor.
- Do not overbake the cookies to maintain a chewy center and prevent dryness.
Nutrition
- Serving Size: 1 cookie
- Calories: 180 kcal
- Sugar: 12 g
- Sodium: 110 mg
- Fat: 8 g
- Saturated Fat: 5 g
- Unsaturated Fat: 3 g
- Trans Fat: 0 g
- Carbohydrates: 25 g
- Fiber: 1 g
- Protein: 2 g
- Cholesterol: 30 mg
