Chewy Fluffernutter Cookies (Peanut Butter and Marshmallow Fluff Cookies!)

Introduction

Imagine the nostalgic taste of a fluffernutter sandwich transformed into a warm, chewy cookie. These cookies combine rich peanut butter with sweet, gooey marshmallow fluff for an irresistible treat that’s both familiar and exciting. You get the perfect chew from a classic dough with a surprising, melty marshmallow center.

This recipe and accompanying image were created with the help of AI for inspiration and guidance. Results may vary depending on ingredients, equipment, and technique.

Prep & Cook Time

Prep Time: 20 minutes
Cook Time: 13 minutes
Total Time: 33 minutes (plus chilling and cooling time)
Servings: 20 cookies

Ingredients

¾ cup unsalted butter (melted)
1¼ cups brown sugar (firmly packed)
2 large eggs (room temperature)
½ teaspoon vanilla extract
⅞ cup creamy peanut butter
2 cups all purpose flour
½ teaspoon baking soda
⅓ teaspoon salt
1 jar Marshmallow fluff ((7 ounces))

Instructions

In a large mixing bowl, whisk together the melted butter and firmly packed brown sugar until smooth and well-combined.
Add the room temperature eggs and vanilla extract to the butter mixture. Whisk vigorously for about 1-2 minutes until the mixture is smooth, slightly thickened, and well-emulsified.
Using a spatula or wooden spoon, mix in the creamy peanut butter until fully incorporated and no streaks remain.
In a separate bowl, whisk together the all-purpose flour, baking soda, and salt.
Cover the bowl with plastic wrap and chill the dough in the refrigerator for at least 1 hour, or up to 24 hours. This is essential for preventing excessive spreading.
Preheat your oven to 350°F (175°C). Line two baking sheets with parchment paper.
Using a cookie scoop or spoon, portion the dough into 20 equal balls (about 2 tablespoons each). Flatten each ball slightly in the palm of your hand.
Create a small, deep well in the center of each dough round. Fill the well with about ½ to 1 teaspoon of marshmallow fluff. Carefully pinch the dough over the fluff to seal it completely inside, rolling gently to form a smooth ball again. Ensure the fluff is fully enclosed to prevent major leaking.
Place the sealed dough balls at least 2 inches apart on the prepared baking sheets. Bake for 11-13 minutes, or until the edges are set and lightly golden. The centers will still look soft.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely. The cookies will firm up as they cool.

Variations

Swirled Top: Instead of fully enclosing the fluff, create a thumbprint indentation after baking for 2 minutes. Fill the indentation with fluff and finish baking. The fluff will set on top.
Chocolate Drizzle: After the cookies are completely cool, drizzle them with melted chocolate for an extra decadent touch.
Sandwich Cookies: Make the cookies slightly smaller and thinner. Once cooled, spread marshmallow fluff between two cookies to create an ultimate fluffernutter sandwich cookie.
Sugar-Coated: Roll the dough balls in granulated sugar before baking for a sparkly, slightly crisp exterior.

Tips for Success

Ensure the fluff is fully sealed inside the dough ball to minimize leakage during baking—some slight oozing is normal and delicious.
Using room temperature eggs helps them incorporate evenly into the butter and sugar mixture, creating a better dough texture.
For consistently sized cookies, use a #40 cookie scoop or a measuring tablespoon to portion the dough.

Storage & Reheating

Store completely cooled cookies in an airtight container at room temperature for up to 3 days. To reheat and restore the gooey texture, microwave a cookie for 10-15 seconds.

FAQ

Can I use natural peanut butter?

My marshmallow fluff leaked everywhere. What happened?

Some minor leaking is normal. Ensure the dough is well-chilled and that you completely seal the fluff inside with no cracks. Using less fluff per cookie can also help.

Can I freeze the cookie dough?

Yes! Prepare the dough balls and freeze them solid on a sheet before transferring to a freezer bag. Bake from frozen, adding 1-2 minutes to the bake time.

Why is the butter melted?

Melted butter contributes to a chewier, denser cookie texture compared to creamed butter, which is perfect for these cookies.

Can I use crunchy peanut butter?

Yes, crunchy peanut butter will work and will add a pleasant texture, though the cookies won’t be as smooth.

My cookies didn’t spread much. Why?

This likely means the dough was over-chilled or packed too firmly. Let the dough balls sit at room temperature for 10 minutes before baking next time.