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These Fluffernutter Cookies are marshmallow-stuffed giant peanut butter cookies stuffed with large marshmallows, then topped with marshmallow fluff and a drizzle of peanut butter for a gooey, peanut buttery fluffernutter experience in cookie form! They’re messy, but definitely worth it.

We love peanut butter and always have some on hand for making some of our favorite desserts! Some of our other favorite peanut butter recipes are No-Bake Peanut Butter Pie, The Ultimate Peanut Butter Swirl Brownies, and Peanut Butter Blondies.

a close image of marshmallow fluff topped peanut butter cookies

Peanut Butter Marshmallow Fluff Cookies

When I was brainstorming foods that Massachusetts is famous for as part of my American Eats series, fluffernutter sandwiches were one of the first things that came to mind. If you have never had or heard of a fluffernutter sandwich, it’s just white bread with peanut butter and marshmallow fluff, much like peanut butter and jelly.

You can even grill them like a grilled cheese sandwich so the peanut butter and fluff get all warm and gooey and the bread is toasty and crisp. They are so good, but not much of a recipe, so I thought instead that I would try using the idea of the fluffernutter to make a different dessert and cookies immediately came to mind.

an overhead image of fluffernutter cookies

It’s kind of a no-brainer since peanut butter and marshmallow go so well together! These cookies are oversized and super shareable, although you can make them smaller if you like. Lately I have really been into giant, Crumbl-sized cookies though and love the wow-factor that you get from them.

They are soft, chewy, and sticky, just like a fluffernutter sandwich, so just embrace the mess and be prepared for a little marshmallow fluff on your fingers and face. You won’t regret it.

large peanut butter cookies covered in marshmallow fluff and peanut butter drizzle

Quick History of Marshmallow Fluff and it’s ties to Massachusetts

The much loved marshmallow fluff had it’s origins in Somerville, Massachusetts back in 1917 but really started taking off in the late 1920’s after a couple of WWI vets joined together to start manufacturing and marketing it. In the 1930’s they even had a radio show to promote Marshmallow Fluff around New England and it’s popularity really took off.

According to one source, the fluffernutter sandwich was invented by an Emma Curtis who was a direct descendant of Paul Revere and called it a “Liberty Sandwich”, possibly in tribute to her ancestor or alternatively because of war meat rationing and using peanut butter as a protein alternative.

You can find fluffernutter bars, fluffernutter ice cream, fluffernutter cupcakes, fluffernutter whoopie pies, fluffernutter fudge, fluffernutter dip, and more. It’ a popular flavor for good reason!

a fluffernutter cookie with a bite taken out of it

Recipe Ingredients

  • Peanut Butter: I only tested this recipe using regular creamy peanut butter rather than a natural peanut butter. If you try it with the kind that you have to store, let me know how it goes! I think chunky peanut butter would work as well if you prefer a little extra crunch.
  • Marshmallow Fluff: While you could make your own, this ingredient with Massachusetts origins makes things a lot easier. You can also use the Kraft Jet-Puffed Marshmallow Cream brand.
  • Marshmallows: I stuff these cookies with large marshmallows for even more marshmallow goodness in every bite!
  • Flour: I use a mix of regular and cake flour which provides the structural basis for these cookies. You can definitely get away with just all-purpose flour if you don’t have any cake flour on hand. Use the spoon-and-sweep method to make sure you are measuring your flour accurately.
  • Butter: Salted butter works great for these cookies and is what I use in almost all of my baking.
  • Sugar: Granulated sugar and brown sugar combine to provide just the right amount of sweetness.
  • Eggs: These bind the cookies and give them a nice chewy texture. The extra egg yolk add richness.
  • Vanilla extract: While vanilla isn’t a dominant flavor, it provides depth to most baking recipes. I love using my homemade vanilla ice cream.
  • Baking powder, baking soda, and salt: These help the cookies puff and spread just the right amount while also not being bland.
ingredients

How to Make Fluffernutter Cookies

  1. Cream butter and sugars: Use a stand mixer fitted with a paddle attachment or hand mixer to beat the butter and sugars until creamy and light.
  2. Add peanut and other ingredients: Beat in the peanut butter, egg and egg yolk, and vanilla extract, then scrape down the bottom and sides of the bowl before mixing in the flours, baking powder, baking soda, and salt.
  1. Scoop and stuff: Use a large cookie scoop to measure out large balls of cookie dough onto a baking sheet lined with parchment paper. Use your thumbs to create a depression in the center of each ball, then stuff with a large marshmallow and wrap the dough around it before placing back on the baking sheet.
  1. Bake: Bake for 12-15 minutes until set around the edges. You don’t want to overbake these cookies or the marshmallow in the center will melt away. Cool on wire racks.
marshmallow stuffed peanut butter cookies on a white surface
  1. Decorate: While these cookies are good just like this, going the extra mile of topping each cookie with a dollop of marshmallow fluff and drizzling them with a little warmed peanut butter really takes them over the top. I just heated the peanut butter for 15-20 seconds in the microwave, then transferred it to a ziploc bag and snipped off one corner to drizzle it over the marshmallow fluff.
a marshmallow stuffed peanut butter cookie with marshmallow fluff on top surrounded by marshmallows and peanut butter

Storage

Keep these cookies in an airtight container in a single layer on the counter. You really can’t stack them since the marshmallow fluff never really hardens or dries, but it’s still worth it to make these if you or someone you know has a fluffernutter obsession.

Leftover cookies will keep on the counter for 4-5 days. You can also freeze these cookies for up to 3 months before topping with marshmallow fluff. Just let them thaw on the counter before topping and serving.

Smaller sizes

These cookies are BIG. Lately that’s been my favorite way of making cookies and I just find it super satisfying. They are in the style of Levain or Crumbl cookies or any other number of gourmet cookie shops.

But you can absolutely make smaller cookies and just stuff them with half a large marshmallow instead. See the recipe notes for adjustments to the bake time.

peanut butter cookies topped with marshmallow fluff next to a bowl of peanut butter

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Fluffernutter Cookies
Yield: 9-12 large cookies

Fluffernutter Cookies

These Fluffernutter Cookies are marshmallow-stuffed giant peanut butter cookies that are then topped with marshmallow fluff and a drizzle of peanut butter for a gooey, peanut buttery fluffernutter experience in cookie form! They're messy, but definitely worth it.

Prep Time 15 minutes
Cook Time 12 minutes
Total Time 27 minutes

Ingredients

  • 1/2 cup cold salted butter, cubed
  • 1/2 cup granulated sugar
  • 1/2 cup light brown sugar, packed
  • 1 and 1/4 cup creamy peanut butter, divided
  • 1 large egg + 1 egg yolk
  • 1 teaspoon vanilla extract
  • 3/4 cup all-purpose flour
  • 3/4 cup cake flour
  • 1/2 teaspoon baking powder
  • 1/2 tsp baking soda
  • 1 teaspoon cornstarch
  • 1/2 teaspoon salt
  • 9-12 large marshmallows
  • 1 jar marshmallow fluff

Instructions

  1. Preheat oven to 400 degrees F. Line two baking sheets with parchment paper.
  2. In the bowl of a stand mixer fitted with a paddle attachment, beat the butter and sugars together for 3-4 minutes until creamy and light. Add 1 cup of the peanut butter, egg, egg yolk, and vanilla, then beat again, scraping down the bottom and sides of the bowl.
  3. Add both types of flour, cornstarch, baking powder, baking soda, and salt, mixing just until combined.
  4. Divide the dough into 9-12 large balls. You can weigh them to be exact, use a large cookie scoop, or just pinch off portions and eyeball it.
  5. Make an indentation in the center of each ball of dough with your thumbs and place a large marshmallow inside. Wrap the dough around the marshmallow, although it's okay if a bit of the marshmallow peaks out.
  6. Space the cookies apart on the baking sheets so they have room to spread. Bake for 13-15 minutes until done. They should be just barely starting to turn golden brown and set around the edges. Be careful not to overbake or the marshmallow inside will melt away and the cookie won't be as soft. Immediately after removing the cookies from the oven while they are still hot, use two spoons to shape the cookies back into circles if they got a little misshapen while baking.
  7. Let the cookies cool on the baking sheet for at least 15 minutes before transferring to a wire rack.
  8. Top each cookie with a spoonful of marshmallow fluff, then drizzle with about 1/4 cup of additional peanut butter that has been warmed in the microwave for 20 seconds and transferred to a ziploc bag with the corner snipped off.

Notes

  • Smaller cookies: As written, these cookies are very large, similar to Crumbl or Levain cookies. If you prefer smaller cookies, you can make 16-18 cookies and just stuff them with 1/2 of a large marshmallow. Bake at a slightly lower temperature of 375 degrees F for 10-12 minutes.
  • Storage: Store in an airtight container at room temperature for up to 5 days.
  • Freezing: They can also be frozen for up to 3 months before adding the marshmallow fluff on top. Thaw at room temperature for at least one hour or heat individual cookies in the microwave and top with the marshmallow fluff before serving.
  • Oven temperature: The reason for the larger size and higher temperature is to cook the outside of the cookie more quickly, leaving the insides slightly on the underbaked side and avoiding the problem of melting the marshmallow entirely. The cookies will continue to set up as you let them cool completely and will even look more set up the next day.
  • Fixing misshapen cookies: A trick to make misshapen cookies look rounded is to use the back of a spoon or two spoons to press the sides in while the cookies are still warm right out of the oven. This only works for the first 60 seconds or so, so you will need to work quickly.

Nutrition Information:

Yield:

9

Serving Size:

1

Amount Per Serving: Calories: 343Total Fat: 15gSaturated Fat: 8gTrans Fat: 0gUnsaturated Fat: 6gCholesterol: 68mgSodium: 350mgCarbohydrates: 49gFiber: 1gSugar: 27gProtein: 5g

All nutritional information is based on third party calculations and is only an estimate. Each recipe and nutritional value will vary depending on the brands you use, measuring methods and portion sizes per household.