Fluffernutter Cookies: How fun! Soft peanut butter cookies sandwiched around a gooey marshmallow filling. Naturally gluten-free & dairy-free.

Fluffernutter cookies stacked on a white plate with cups of coffee in the background.

Give me all the peanut butter desserts!

I just can’t get enough.

Peanut butter blondies, peanut butter blossoms, peanut butter fudge, peanut butter pie

I’ve got a fever, and the only prescription is more peanut butter.

 

I know I’m not alone in this, right? Peanut butter and chocolate are the ultimate combination…

With the possible exception of peanut butter and marshmallow, like what we have here today in these incredible fluffernutter cookies!

WHAT DOES “FLUFFERNUTTER” MEAN?

Fluffernutter = peanut butter + marshmallow.

Get it? “Fluffer” for marshmallow fluff, and “nutter” for peanut butter.

And just hearing that word takes me straight back to my childhood!

I can remember so many of my schoolmates bringing fluffernutter sandwiches to school. Sadly I was never allowed to eat them. So as you can see I’m now making up for the resulting sugar deficiency in my adulthood!

Peanut butter marshmallow cookies on a white plate with a text overlay above that reads "Fluffernutter Cookies."

WHAT ARE FLUFFERNUTTER COOKIES?

Fluffernutter cookies were inspired by that childhood staple: the fluffernutter sandwich.

In this version, I’ve taken two soft peanut butter cookies and filled them with my homemade marshmallow fluff.

If you’re thinking gee, that sounds pretty fantastic, you’d be right. You’ve gotta make these, this weekend!

HOW TO MAKE FLUFFERNUTTER COOKIES

There are two main components to this recipe:

  1. flourless peanut butter cookies, and
  2. gooey marshmallow filling.

Let’s start with the cookies!

THE PEANUT BUTTER COOKIES

This is my FAVORITE peanut butter cookie recipe ever, because it bakes up so soft and tender, with SO MUCH peanut butter flavor. They’re just sweet enough, with a little bit of a savory edge.

I’ve got lots of info about the recipe here: Peanut Butter Cookies, but it’s pretty simple really.

Basically, you just stir peanut butter, sugar, eggs, baking soda, and salt together…

Overhead Image of a bowl of peanut butter cookie dough.

Then scoop onto baking sheets, press with the tines of a fork…

Unbaked peanut butter cookies on a baking sheet.

And bake!

Peanut butter cookies on a tray lined with parchment.

That’s it! Just 5 simple ingredients.

THE MARSHMALLOW FILLING

While the peanut butter cookies are baking, you can get going on the filling.

It’s basically just this Marshmallow Frosting recipe <-- so click here for lots more info if you have any questions. You'll want to start by gently whipping egg whites, cream of tartar, and salt together until they start to look foamy. Then, whip in sugar, v-e-r-y S-L-O-W-L-Y, until you have a soft meringue. Add a dash of vanilla for that signature marshmallow flavor, and whip it like crazy until it can hold stiff peaks. Whipping marshmallow filling in a stand mixer.

The final step is to cook a sugar-water mixture until it reaches 235 degrees F. If you don’t already have a thermometer, here’s a link to the kind I like: Digital Thermometer.

Once the syrup hits temperature, drizzle it slowly into the meringue while whipping.

Not only does this sweeten the filling, but it also makes it more stable and marshmallow-y, as well as cooking the egg whites.

Sandwiching peanut butter cookies with marshmallow filling.

Pipe or spoon a generous dollop of this sweet & gooey filling on the bottom of one cookie, then sandwich another on top.

Fluffernutter sandwich cookies on a ruffled white plate with a checked napkin.

Ta-dah!

ALLERGEN-FREE INGREDIENT SUBSTITUTIONS

This recipe contains zero flour and no dairy either, so it’s naturally gluten-free and dairy-free.

But it does contain eggs, so it’s not vegan. I have not tried making a vegan version, so I can’t say for sure, but I would imagine you could probably substitute aquafaba for the egg whites. If you try it I’d love to hear about the results!

If you are looking to make a nut-free version of this recipe, I would suggest using sunflower seed butter in place of the peanut butter. It tastes so much like peanut butter, but allergen-free.

Marshmallow fluff cookies broken in half with gooey filling displayed.

HOW TO STORE

These cookies are probably best eaten the first day or so.

After a little while, the filling may start to lose volume and soak into the cookies. Not that that’s such a bad thing! I think they’d still taste darn good.

While optimal when fresh from the oven, these can be kept in an airtight container for around 3 to 5 days.

Close-up image of fluff cookies showing off marshmallow filling sandwiched between peanut butter cookies.

A FEW MORE OF MY FAVORITE COOKIE AND BAR RECIPES

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Fluffernutter Cookies
Prep Time
25 mins
Cook Time
20 mins
Cooling Time:
30 mins
Total Time
1 hr 15 mins
 

Fluffernutter Cookies: How fun! Soft peanut butter cookies sandwiched around a gooey marshmallow filling. Naturally gluten-free & dairy-free.

Course: Dessert, Snack
Cuisine: American
Keyword: fluffernutter cookies, peanut butter fluffernutter cookies, peanut butter marshmallow cookies
Servings: 18 sandwich cookies
Calories: 332 kcal
Ingredients
For the Peanut Butter Cookies:
For the Marshmallow Filling:
Instructions
To Make the Peanut Butter Cookies:
  1. Preheat the oven to 350 degrees F and line baking sheets with parchment paper.

  2. Place the peanut butter, sugar, baking soda, salt, and eggs in a large mixing bowl and stir together until combined.

  3. Scoop 1 1/2 tablespoon-sized balls of dough on to the prepared baking sheets.

  4. Press the balls down with the tines of a fork.

  5. Bake for 9 to 12 minutes, or until set around the edges but still soft in the middle.

  6. Allow to cool on the baking sheet for 10 minutes (cookies will be very tender while warm).

  7. Sandwich with marshmallow filling & serve.

To Make the Marshmallow Filling:
  1. Place the egg whites, cream of tartar, and salt in a large mixing bowl and whip on medium speed until foamy.

  2. While continuing to whip, add 1 cup of the sugar in a very slow and steady stream (about 1 teaspoon at a time).

  3. Once the entire cup of sugar has been added, continue to whip until the meringue can hold stiff peaks.

  4. Whip in the vanilla extract, and continue to stir the meringue on low speed while you prepare the hot sugar syrup.

  5. Place the remaining 1 cup of sugar in a small pot, along with the water.

  6. Place the pot over medium heat and cook until the syrup boils and reaches 235 degrees F.

  7. In a very slow and steady stream, add the hot sugar syrup to the meringue, while continuing to whip on low speed.

  8. When all the syrup has been added, turn the mixer up to high speed and whip until very stiff and glossy.

Recipe Video

Recipe Notes

*A few drops of lemon juice or white vinegar may be substituted. 

Nutrition Facts
Fluffernutter Cookies
Amount Per Serving (1 sandwich cookie)
Calories 332 Calories from Fat 135
% Daily Value*
Fat 15g23%
Saturated Fat 3g19%
Trans Fat 1g
Polyunsaturated Fat 4g
Monounsaturated Fat 7g
Cholesterol 18mg6%
Sodium 420mg18%
Potassium 222mg6%
Carbohydrates 45g15%
Fiber 2g8%
Sugar 42g47%
Protein 9g18%
Vitamin A 26IU1%
Calcium 16mg2%
Iron 1mg6%
* Percent Daily Values are based on a 2000 calorie diet.