Soft and Chewy Fluffernutter Cookies are the kind of peanut butter cookie that feels playful, nostalgic, and bakery-worthy all at once. They bake up thick and tender with creamy peanut butter flavor, pockets of marshmallow sweetness, and that soft middle everyone hopes for when reaching into the cookie jar.

This is a cozy cookie for bake sales, lunchbox treats, weekend baking, or the moment you want something sweet without making a complicated dessert. The combination of peanut butter and marshmallow fluff gives each bite that classic fluffernutter flavor while keeping the texture chewy, rich, and slightly gooey in the center.

Why You’ll Love This Soft and Chewy Fluffernutter Cookies

These cookies are soft in the center, lightly golden at the edges, and filled with the sweet peanut butter-marshmallow flavor that makes fluffernutter desserts so comforting. They taste like a childhood sandwich turned into a warm cookie, but with enough texture and richness to feel special.

You will also love how simple the dough is to work with. The peanut butter gives it body, the brown sugar helps create chewiness, and small swirls of marshmallow fluff make every cookie a little different. They do not need fancy decorating, chilling for hours, or hard-to-find ingredients. A tray of these cookies looks homemade in the best way, especially when the tops crack slightly and the marshmallow peeks through.

They are also easy to share. This batch makes about 24 cookies, which is perfect for family dessert, cookie boxes, parties, or a sweet treat to keep on hand during the week.

What Makes Fluffernutter Cookies So Soft and Chewy?

The secret is the balance of fat, sugar, peanut butter, and baking time. Creamy peanut butter adds richness and structure, while brown sugar brings moisture and a deeper caramel-like sweetness. A little granulated sugar helps the edges set without making the cookies crisp all the way through.

Marshmallow fluff adds that signature fluffernutter sweetness, but it also creates tender, gooey spots in the dough. The key is to fold or swirl it in gently instead of fully mixing it. When the fluff stays in little ribbons, the cookies bake with soft pockets rather than disappearing into the dough.

For the best texture, pull the cookies from the oven when the edges look set but the centers still look slightly soft. They will continue to finish on the hot baking sheet, giving you that chewy middle instead of a dry cookie.

Ingredients for the Soft and Chewy Fluffernutter Cookies

Each ingredient plays a small but important role in creating cookies that are tender, sweet, nutty, and full of marshmallow flavor. The exact quantities are saved for the printable recipe card below, but here is what you will need and why it matters.

Creamy peanut butter: This gives the cookies their classic nutty base and helps create a rich, soft dough. Use a shelf-stable creamy peanut butter for the most consistent texture.

Unsalted butter: Butter adds flavor and tenderness. Softened butter also creams well with the sugars, helping the cookies bake up lighter instead of dense.

Brown sugar: Brown sugar keeps the cookies chewy and adds a warm sweetness that pairs beautifully with peanut butter.

Granulated sugar: A little granulated sugar balances the brown sugar and helps the cookie edges set nicely.

Egg: The egg binds the dough and gives the cookies structure so they stay soft without falling apart.

Vanilla extract: Vanilla rounds out the peanut butter flavor and makes the marshmallow taste warmer and sweeter.

All-purpose flour: Flour gives the cookies their shape and body. Measuring it properly helps prevent dry or cakey cookies.

Baking soda: Baking soda helps the cookies spread gently and gives them a tender bite.

Salt: Salt balances the sweetness and makes the peanut butter flavor stronger.

Marshmallow fluff: This is the heart of the fluffernutter flavor. It adds sweet, gooey ribbons throughout the dough.

Mini marshmallows: These add soft, melty pockets and a fun visual touch. They work best when tucked partly inside the dough so they do not overbrown.

Chopped peanuts, optional: Peanuts add crunch and a little salty contrast if you want more texture.

How To Make the Soft and Chewy Fluffernutter Cookies

The method is simple, but a few small details help keep the cookies thick, soft, and full of visible marshmallow swirls. Do not overmix once the flour goes in, and be gentle when adding the marshmallow fluff.

Step 1: Prepare the Baking Sheets

Preheat the oven and line your baking sheets with parchment paper. Parchment helps keep the marshmallow from sticking and makes cleanup easier. Give each cookie enough space because the dough will spread a little as it bakes.

Step 2: Cream the Butter, Peanut Butter, and Sugars

In a large mixing bowl, beat the softened butter, creamy peanut butter, brown sugar, and granulated sugar until the mixture looks smooth and fluffy. This step helps create a softer cookie texture, so give it enough time to become creamy rather than just mixed.

Step 3: Add the Egg and Vanilla

Beat in the egg and vanilla extract until the mixture is fully combined. Scrape down the sides of the bowl so the peanut butter mixture stays even from top to bottom.

Step 4: Mix the Dry Ingredients

In a separate bowl, whisk together the flour, baking soda, and salt. Add the dry ingredients to the wet ingredients and mix just until the dough comes together. Stop as soon as you no longer see dry flour, because overmixing can make the cookies tougher.

Step 5: Swirl in the Marshmallow Fluff

Drop small spoonfuls of marshmallow fluff over the dough. Fold it in gently with a spatula, leaving visible streaks instead of blending it completely. This is what gives the cookies those gooey fluffernutter pockets.

Step 6: Add Mini Marshmallows

Fold in the mini marshmallows gently. If some marshmallows sit on the outside of the dough balls, press them slightly into the dough so they melt into the cookies rather than puffing too much on the pan.

Step 7: Scoop the Dough

Scoop the dough into rounded portions and place them on the prepared baking sheets. For thicker cookies, keep the scoops tall rather than flattening them. Add chopped peanuts on top if you want a salty crunch.

Step 8: Bake Until Soft and Set

Bake until the edges are lightly golden and the centers still look slightly soft. The cookies should not look fully firm when they leave the oven. Let them rest on the baking sheet for several minutes so they can finish setting without losing their chewy centers.

Step 9: Cool and Enjoy

Move the cookies to a wire rack once they are sturdy enough to lift. Enjoy them slightly warm for the softest marshmallow pockets, or let them cool completely for a chewy cookie jar texture.

How to Serve Soft and Chewy Fluffernutter Cookies

This recipe makes about 24 cookies, serving around 12 people if you plan on two cookies per person. They are rich and sweet, so they fit beautifully on a dessert tray with coffee, cold milk, hot chocolate, or a scoop of vanilla ice cream.

Serve them slightly warm when you want the marshmallow ribbons to feel gooey and soft. For a party platter, let them cool fully so they stack neatly and hold their shape. You can also turn them into ice cream sandwiches by pairing two cooled cookies with peanut butter, vanilla, or chocolate ice cream.

For lunchboxes or gifting, place parchment between layers so the marshmallow spots do not stick. These cookies are also lovely for holiday cookie boxes because they bring a different flavor from the usual chocolate chip or sugar cookie.

How to Store Soft and Chewy Fluffernutter Cookies

Store cooled cookies in an airtight container at room temperature for up to 4 days. Because marshmallow can be sticky, layer parchment paper between the cookies if stacking them. A small piece of sandwich bread in the container can help keep the cookies soft, but remove it once it begins to dry out.

For longer storage, freeze the baked cookies in a freezer-safe container for up to 2 months. Place parchment between layers and let them thaw at room temperature before serving. You can warm a cookie for a few seconds in the microwave to bring back the soft, gooey texture.

The dough can also be frozen before baking. Scoop the dough into balls, freeze them on a tray until firm, then transfer them to a freezer bag. Bake from frozen, adding an extra minute or two as needed. For best results, keep marshmallow pieces tucked into the dough balls before freezing so they bake evenly.

Avoid refrigerating baked cookies unless your kitchen is very warm. The refrigerator can make cookies taste dry faster, while room-temperature storage keeps them softer.

Frequently Asked Questions

Can I use natural peanut butter for Soft and Chewy Fluffernutter Cookies?

Shelf-stable creamy peanut butter works best because it has a consistent texture and helps the cookies hold their shape. Natural peanut butter can separate and may make the dough oily, crumbly, or too loose. If you only have natural peanut butter, stir it extremely well before measuring and expect the texture to be slightly different.

How do I keep the marshmallow fluff from disappearing into the dough?

Add the marshmallow fluff at the very end and fold it only a few times. You want visible streaks, not a fully blended dough. If the fluff is mixed in completely, the flavor will still be there, but you will lose those gooey ribbons that make the cookies look and taste special.

Why did my marshmallows melt out of the cookies?

Marshmallows can melt and spread if they are exposed directly to the hot pan. Try pressing them gently into the dough balls before baking. Parchment paper also helps prevent sticking. If a little marshmallow melts around the edges, let the cookies cool on the pan before moving them so the melted sugar can firm up.

Can I make the dough ahead of time?

Yes, you can make the dough ahead and chill it for up to 24 hours. Let it sit at room temperature for a few minutes before scooping if it becomes too firm. You can also freeze scooped dough balls for future baking, which is great when you want fresh cookies without starting from scratch.

Can I add chocolate chips to these cookies?

Absolutely. Chocolate chips taste wonderful with peanut butter and marshmallow. Semi-sweet chocolate chips keep the cookies balanced, while milk chocolate makes them sweeter and more candy-like. Start with a modest amount so the fluffernutter flavor still shines.

If you love these soft peanut butter marshmallow cookies, you’ll probably enjoy these other sweet bakes from Life With Mira:

• Soft Pumpkin Snickerdoodles with Cinnamon Sugar for a cozy spiced cookie with a tender bite.

• Winter Wonderland Chocolate Chip Christmas Cookies when you want a festive cookie tray favorite.

• Oreo Stuffed Cinnamon Rolls for a playful cookies-and-cream breakfast treat.

• Red Velvet Cheesecake Brownies if you love soft dessert bars with a creamy swirl.

Save This Pin For Later

📌 Save these Soft and Chewy Fluffernutter Cookies to your Pinterest dessert board so you can come back to them whenever a peanut butter-marshmallow craving hits.

And let me know in the comments how yours turned out. Did you add chocolate chips, sprinkle chopped peanuts on top, or keep them classic with just peanut butter and marshmallow?

I love hearing how others make these cookies their own. Questions are welcome too, so we can help each other bake softer, chewier cookies every time. For more daily recipe inspiration, follow Life With Mira.

Soft and Chewy Fluffernutter Cookies