Sweet Potato Fluff
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This baked sweet potato fluff is a delicious, elegant, sweet potato casserole. Topped with homemade marshmallow fluff, it features gently-toasted, glossy peaks and swirls. This photogenic side is a joy to serve on Thanksgiving Day.

There’s so much to love about this easy recipe. This beautiful fall classic has the perfect balance of sweet and savory. It’s tender and buttery, aromatic and comforting. Easy to transport, it’s ideal for bringing to potlucks.
Make sweet potato fluff a Thanksgiving or Friendsgiving tradition!
Craving a nutty crunch on your sweet potato casserole? Before adding the marshmallow topping, sprinkle a thin even layer of toasted pecans over the potatoes. [NOTE: If taking this dish to a potluck, it’s wise to skip the nuts. There are a lot of people with nut allergies.]

🛒 INGREDIENTS
This holiday favorite comes together with just a few common ingredients. For large gatherings, purchase twice the ingredients to double the recipe.
SWEET POTATO CASSEROLE
- Sweet potatoes
- Light brown sugar
- Butter
- Pumpkin pie spice
- Vanilla extract
- Sea salt
- Heavy cream

MARSHMALLOW FLUFF TOPPING
- Water
- Granulated sugar
- Corn syrup
- Pasteurized egg whites, like Bob Evan’s brand*
- Cream of tartar
- Sea salt
- Vanilla extract
* PASTEURIZED EGG WHITES: Pasteurization kills bacteria in fresh eggs that can cause food-borne illness. Find a pourable carton of this product at the market in the refrigerated section next to the eggs.

🥣 easy ingredient swaps
Missing an ingredient for baked sweet potato casserole with marshmallow fluff? Don’t put on your shoes and head to the market. Instead head to your fridge and pantry. Check for these easy ingredient substitutions.
It’s convenient (and money-saving) to use ingredients you already have on hand.
- Brown Sugar: Use dark brown sugar or granulated sugar.
- Butter: The best swap is margarine.
- Pumpkin Pie Spice: Use ground cinnamon. Or for a homemade version of pumpkin pie spice: ground cinnamon plus a pinch of each: ground nutmeg, ground ginger, ground all spice, and ground cloves.
- Heavy Cream: If you don’t have this ingredient on hand, you can skip it!
- Cream of Tartar: This ingredient stabilizes egg whites and prevents sugar from crystalizing (1/8 teaspoon per egg white). It’s what gives meringue its tall characteristic peaks. Best swap: 1 teaspoon lemon juice or vinegar for every 1/2 teaspoon cream of tartar.
- Granulated Sugar: Use light-brown sugar.
- Corn Syrup: Use honey instead.
- Vanilla Extract: Replace with maple syrup, brandy, bourbon or rum.

📖 recipe steps
For best results, read recipe instructions all the way through. Get familiar with the steps before starting the recipe.
BAKED SWEET POTATO CASSEROLE
RECIPE PREP: Preheat oven to 400°F. Line a rimmed baking tray with foil. Pull out a 9×9 casserole dish. Butter the bottom and halfway up the sides.

- STEP 1: Rinse sweet potatoes. Pat them dry between paper towels. Put them on lined baking sheet. Pierce each potato 4 times with a fork. Depending on size and thickness, bake 45 to 60 minutes, or until fork tender and super soft. [See helpful multi-tasking hint below.*] Remove pan from oven.
- STEP 2: Use a lint-free cloth to grip hot potatoes. Slice them in half lengthwise. With a metal spoon, scoop out the soft tender flesh and transfer it to a medium bowl or a food processor. Discard the skins.
- STEP 3: Put butter in a ramekin. Melt it in the microwave. Mash (or process) the hot potatoes until smooth. Add butter, sugar, pumpkin pie spice, sea salt, vanilla, and heavy cream. Mix and mash until all ingredients are fully incorporated.
- STEP 4: Transfer mashed potatoes to prepared casserole dish. With a spoon or spatula, spread the mixture into an even layer.
*HOW TO MAKE THIS RECIPE FASTER: After sweet potatoes have been baking for 30 minutes, start assembling marshmallow fluff.

MARSHMALLOW FLUFF TOPPING
RECIPE PREP: Make triple sure mixing bowl and whip are free of grease. They must be meticulously clean. If there’s even a tiny speck of grease, it will prevent the egg whites from whipping.
- STEP 1: In a stand mixer with whisk attachment, whisk together egg whites and cream of tartar until soft peaks form, about 3 to 4 minutes. While the mixer is whisking, start prepping sugar syrup on stovetop.
- STEP 2: Combine water, granulated sugar, corn syrup and salt in a medium saucepan over medium-high heat. Bring to a boil for 8 to 10 minutes, stirring constantly. The boiling is important for thick marshmallow fluff. Don’t leave mixture unattended. It can boil over and/or burn.
- STEP 3: With the stand mixer on medium-low setting, carefully (in a slow, thin steady stream) pour the hot sugar syrup into the egg whites. Once hot liquid is all in the bowl, add vanilla extract.
- STEP 4: Turn speed to high. Mix 7 to 8 minutes. You’ll notice ripple indentions on the surface. Keep going. We’re looking for deep grooves and creases extending from the surface down to the bottom of the bowl.

👩🏻🍳 HOW TO KNOW WHEN MARSHMALLOW FLUFF IS DONE: Mixture should be billowy, thick and glossy. Turn off mixer. Lift metal whip. If marshmallow fluff grips the whip and forms a pointed peak at the end, the mixture is done.

ASSEMBLE SWEET POTATO FLUFF
Spoon dollops of marshmallow fluff over the sweet potatoes. Gently spread it into a rough layer but not all the way to the edges. Leave 1/2 inch of the orange layer visible. With the back of a spoon, form decorative peaks. Use a combination of gentle swirling and lifting motions to achieve desired look.

With a kitchen torch lightly toast the marshmallow fluff. It toasts up super quick. Be careful not to scorch it. No culinary torch? See instructions for toasting without a butane torch in the “Recipe FAQ” section on this page.
🧑🏼🍳 RECIPE FAQ
These are the most commonly asked questions when making sweet potato fluff, and the most helpful answers for recipe success!
No, they’re not. It can be confusing. At the market yams are often labeled “sweet potatoes.” However, a sweet potato has a smooth, light-orange appearance with tapered ends. The flesh is generally dark orange and moist. A yam, on the other hand, has dark-brown, bark-like skin and dry starchy flesh. Sweet potatoes are sweet. Yams are not.
No. The store-bought product becomes flat and runny when topping a warm sweet potato casserole. It will ruin the photogenic appearance of this beautiful Thanksgiving side.
Yes! If you don’t have ingredients to make marshmallow fluff, sprinkle 2 cups mini marshmallows over the baked sweet potato casserole. Bake 15 minutes, or until marshmallows are lightly toasted.
Yes for the sweet potatoes, but no for the topping. For the sweet potato casserole, bake a double batch of the veggies on 2 baking trays on 2 oven racks. Assemble marshmallow fluff in two separate batches. Don’t double this part of the recipe. The egg whites need a large bowl with a lot of space to get fluffy when whipped.
Yes, it is! Sweet potato fluff is an easy make-ahead recipe. Assemble sweet potato casserole (without topping), cover and refrigerate. Assemble the marshmallow fluff and transfer to an air-tight container. Before serving, re-warm the casserole. If needed, the topping can be re-whipped! Spread fluff over the top and toast the peaks and swirls.
This is one of the top tips for making marshmallow fluff. Room temperature egg whites produce maximum volume and fluffiness. The whipped whites can actually expand up to 8 times their volume.
Thoroughly clean the kitchen tools with warm water and dish soap. Dry them well with a clean, lint-free kitchen towel. Another method: wipe them down with lemon juice using a lint-free cloth.
Transfer topping to a piping bag fitted with a metal tip of your choice. Pipe beautiful swirls across the surface of the sweet potato casserole.
Use the oven! Broil sweet potato casserole VERY BRIEFLY until topping is slightly toasty. Have potholders at the ready. Keep a close eye on the marshmallow fluff. It toasts up very quickly.
Find several good-quality culinary torches online for around $20. So affordable! In the recipe card, there’s an Amazon affiliate link for a great one. You can also check the kitchen section of your local hardware store. They’re often on a shelf next to the butane fuel canisters.
The casserole with marshmallow topping can stay fresh for up to 5 days.
When stored in an airtight container, it can stay fresh at room temperature (about 68°F) for up to 2 weeks. If needed, re-whip to restore fluffiness. For longer storage, freeze up to 1 month.
Yes! Store sweet potato casserole and marshmallow fluff separately in an airtight containers and freeze. When ready to enjoy, defrost in the fridge overnight. Transfer casserole to a baker and reheat in a 350°F oven until warm. If needed, re-whip defrosted marshmallow fluff. Spread topping over casserole. Toast with a butane torch.

🦃 more thanksgiving recipes
If you loved sweet potato fluff, you’ll enjoy these fall recipes too! Add this group of tried-and-true favorites to your Thanksgiving recipe arsenal.
- Green Beans Almondine
- Cheesy Scalloped Potatoes
- Homemade Gravy
- Best Jiffy Cornbread
- Baking Powder Biscuits
- Parker House Rolls
- Pumpkin Hummus
- Tiramisu

RATE THIS RECIPE ⭐️⭐️⭐️⭐️⭐️
Friends and family who’ve enjoyed this baked sweet potato casserole for Thanksgiving have raved over and over about how delicious it is.
If you too enjoyed my yummy sweet potato fluff and thought it was awesome, give it a 5-star rating in the comments. Then be a recipe hero. Share this holiday favorite with a friend or two!


SWEET POTATO FLUFF
- Total Time: 1 Hour 10 Minutes
- Yield: 9 Servings 1x
Description
Grace your Thanksgiving holiday table with sweet potato fluff. This delicious casserole is a photogenic side with a topping that features homemade marshmallow fluff with toasted peaks and swirls.
Ingredients
BAKED SWEET POTATO CASSEROLE
- 5 sweet potatoes
- 1/2 cup (packed) light brown sugar
- 1/3 cup butter (plus more for buttering dish)
- 1 1/2 teaspoons pumpkin pie spice
- 1/2 teaspoon vanilla extract
- 1/2 teaspoon sea salt
- 2 tablespoons heavy cream
MARSHMALLOW FLUFF TOPPING
- 1/3 cup water
- 3/4 cup granulated sugar
- 3/4 cup corn syrup
- 1/2 cup pasteurized egg whites, room temperature *
- 1 teaspoon cream of tartar
- 1/4 teaspoon sea salt
- 1 teaspoon vanilla extract
* PASTEURIZED EGG WHITES: Pasteurization kills bacteria in fresh eggs that can cause food-borne illness. Find a pourable carton of this product (like Bob Evan’s brand) at the market in the refrigerated section next to the eggs. One-half cup pasteurized egg whites is equal to separated egg whites from 4 large eggs.
Instructions
SWEET POTATO CASSEROLE
RECIPE PREP: Preheat oven to 400°F. Line a rimmed baking sheet with foil. Pull out a 9×9 casserole dish. Butter the bottom and halfway up the sides.
- Rinse sweet potatoes. Pat them dry between paper towels. Put them on prepared baking sheet. Pierce each potato 4 times with a fork. Depending on size and thickness, bake 45 to 60 minutes or until fork tender and super soft. [See helpful multi-tasking hint below.*] Remove pan from oven.
- Use a lint-free cloth to grip potatoes. Slice them in half lengthwise. With a metal spoon, scoop out soft tender flesh and transfer it to a medium bowl or a food processor. Discard skins.
- Put butter in a ramekin. Melt it in the microwave. Mash (or process) the hot potatoes until smooth. Add butter, sugar, pumpkin pie spice, sea salt, vanilla, and heavy cream. Mix and mash until all ingredients are fully incorporated.
- Transfer mashed potatoes to prepared casserole dish. With a spoon or spatula, spread the mixture into an even layer.
*HOW TO MAKE THIS RECIPE FASTER: After sweet potatoes have been baking for 30 minutes, start assembling marshmallow fluff.
MARSHMALLOW FLUFF TOPPING
RECIPE PREP: Make triple sure mixing bowl and whip are free of grease. They must be meticulously clean. If there’s even a tiny speck of grease, it will prevent the egg whites from whipping.
- In a stand mixer with whisk attachment, whisk together egg whites and cream of tartar until soft peaks form, about 3 to 4 minutes. While the mixer is whisking, start prepping sugar syrup on stovetop.
- Combine water, granulated sugar, corn syrup and salt in a medium saucepan over medium-high heat. Bring to a boil for 8 to 10 minutes, stirring constantly. The boiling is important for thick marshmallow fluff. Don’t leave mixture unattended. It can boil over and/or burn.
- With the stand mixer on medium-low setting, carefully (in a slow, thin steady stream) pour the hot sugar syrup into the egg whites. Once hot liquid is all in the bowl, add vanilla extract.
- Turn speed to high. Mix 7 to 8 minutes. You’ll notice ripple indentions on the surface. Keep going. We’re looking for deep creases and valleys extending vertically from the surface down to the bottom of the bowl. Mixture should be very thick and glossy. Turn off mixer. Lift metal whip. If marshmallow fluff grips the whip and forms a pointed peak at the end, the mixture is done.
ASSEMBLE SWEET POTATO FLUFF
- Spoon dollops of marshmallow fluff over the sweet potatoes. Gently spread it into a rough layer but not all the way to the edges. Leave 1/2 inch of the orange layer visible. With the back of a spoon, form decorative peaks. Use a combination of gentle swirling and lifting motions to achieve desired look.
- With a kitchen torch lightly the marshmallow fluff. It toasts super quick, so be careful. No culinary torch? No problem! See instructions for toasting without a butane torch in the “Recipe FAQ” section on this page.
RECIPE TIP: If you want to elevate the look of the topping, transfer marshmallow fluff to a piping bag fitted with a metal tip of your choice. Pipe gorgeous swirls over the surface of the casserole.
- Prep Time: 20 Minutes
- Cook Time: 50 Minutes
- Category: Side Dish
- Method: Bake
- Cuisine: American
Keywords: Sweet Potato Fluff, Sweet Potato Casserole

SWEET POTATO FLUFF > JOIN THE CONVERSATION
Does your Thanksgiving menu include sweet potato casserole? What do you think of this photogenic version with homemade marshmallow fluff? Share your thoughts on baked sweet potato fluff in the comments below!
What a unique and delicious recipe to try with sweet potato. I love the fluffy homemade topping. Great instructions to make things simple. Thanks for sharing!
★★★★★
Now this is a unique dessert recipe!I’ve never tried this before. I can imagine how flavorful this dessert is! Thanks for this.
★★★★★
Wow, what a unique way to serve sweet potato. My husband is going to love this. Perfect for fall, all season long.
★★★★★
Love this version of a traditional sweet potato casserole! Definitely adding it to my list of Thanksgiving recipes to make this year!
★★★★★
I loved the recipe and found it very easy to follow! Thanks!
★★★★★