Classic Sweet Potato Casserole
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This easy sweet potato casserole with marshmallows comes together with just 6 ingredients. A buttery sweet potato filling and golden marshmallow topping make it a Thanksgiving favorite.

I grew up loving my mom’s pecan-topped sweet potato casserole, which inspired my healthy sweet potato casserole, but Isaac requests the marshmallow version every year. I finally gave it a try, and honestly? The slightly crisp edges on those toasted marshmallows won me over! For my version, I roast the sweet potatoes before mashing them because I love the flavor they bring to the filling, then keep the additions simple with butter, sugar and vanilla.
Table of Contents
- Why You’ll This Sweet Potato Casserole
- Ingredients Needed
- Substitutions & Variations
- How to Make Sweet Potato Casserole
- Brittany’s Tips!
- What to Serve with Sweet Potato Casserole
- How to Make Ahead
- How to Store Leftovers
- Frequently Asked Questions
- More Sweet Potato Recipes to Try
- Marshmallow-Topped Sweet Potato Casserole Recipe
“Soooo yummy! Made this today along with the healthy sweet potato casserole to decide which to make for Thanksgiving. The kids LOVED this one! Perfect balance of sweet and savory and pretty easy to put together. Highly recommend this one!”
Why You’ll This Sweet Potato Casserole

- That toasted marshmallow topping: Golden on top and gooey underneath, it’s the part you’ll want in every bite.
- No eggs needed: There’s no egg to beat or temper, and no milk or cream to add.
- Simple equipment: A fork or potato masher does the job, so you can skip getting out the mixer.
Ingredients Needed

- sweet potatoes – choose orange-fleshed sweet potatoes, such as Jewel or Garnet, with firm skins and no soft spots.
- coconut sugar or brown sugar – either works here. Brown sugar adds molasses flavor, while coconut sugar brings a caramel-like sweetness.
- unsalted butter – adds richness and lets you control the salt separately.
- sea salt – balances the sweetness of the potatoes and marshmallow topping.
- vanilla extract – adds a warm vanilla flavor. Use pure vanilla extract if you have it.
- mini marshmallows – their small size makes it easy to cover the filling evenly. Choose gelatin-free marshmallows if you need the casserole to be vegetarian.
Find the full ingredient list with measurements in the recipe card below.
Substitutions & Variations
- Make it vegan: Since this recipe doesn’t have any eggs, milk or heavy cream you can easily make it vegan by using vegan butter and vegan marshmallows like these Dandies mini marshmallows.
- Add pecans: If you’re like me and love pecans, you can sprinkle 1/4 cup pecans on top of the sweet potato mixture with the marshmallows.
- Add cinnamon: For some spice and added warmth sprinkle some ground cinnamon on top of the casserole.
How to Make Sweet Potato Casserole

Step 1: Pierce the sweet potato 4-6 times with a fork. Place potato on a baking sheet and bake at 400ºF for about 45-65 minutes.

Step 2: Once your sweet potatoes are fork-tender peel and transfer the flesh to a large bowl. Use a fork or potato masher to mash the sweet potatoes until smooth and creamy.

Step 3: Add sugar, butter, salt and vanilla to the potatoes and stir to combine.

Step 4: Transfer mixture to a baking dish, top with marshmallows and bake for 20-25 minutes at 375ºF .
Brittany’s Tips!
- Check the center: A fork should slide easily through the thickest part of each potato. If there’s resistance, keep roasting so you don’t end up with firm bits in the filling.
- Drain thoroughly if boiling: Let the cooked potatoes drain well before mashing. Water clinging to the potatoes can make the filling loose.
- Watch closely when broiling: For extra browning, use a broiler-safe dish and watch constantly. Marshmallows can go from toasted to burnt quickly.
What to Serve with Sweet Potato Casserole
For a smaller holiday dinner, serve this casserole with my air fryer turkey breast. It leaves the oven available for your sides! Add healthy green bean casserole for something savory and cranberry sauce for a tart bite between forkfuls.

How to Make Ahead
Prepare the sweet potato filling up to 2 days ahead and spread it in your baking dish. Cover and refrigerate without the marshmallows.
When you’re ready to bake, heat the filling covered at 375°F until hot throughout, then uncover, add the marshmallows and bake until golden. Allow extra time for the chilled filling, and use a baking dish suitable for refrigerator-to-oven use.
How to Store Leftovers
Storage: Cover and refrigerate leftovers for 3–4 days. The marshmallow topping will soften and gradually melt into the filling as it sits.
Reheat individual portions in the microwave or a larger amount in an oven-safe dish at 350°F until hot throughout.
Frequently Asked Questions
For the best topping texture, freeze the casserole without the marshmallows. Bake the filling, let it cool, cover tightly and freeze for up to 3 months. Thaw overnight in the refrigerator, then follow the make-ahead reheating instructions above.
The method used to cook your sweet potatoes is totally a personal preference. I love the flavor baked sweet potatoes add to this dish, but I’ve also boiled them before and both have turned out awesome. You can also cook your potatoes in an Instant Pot or in the microwave if you’re short on time!
Many grocery stores use the terms “yam” and “sweet potato” interchangeably, but the two are actually quite different. Real yams have rough brown skin, starchy white flesh and a long, cylinder shape. Sweet potatoes usually have smooth, thin orange skin with orange, white or purple flesh. They’re shorter and wider than yams and have a much sweeter taste.
Even if you buy a “yam” at the grocery store you’re more than likely actually buying a sweet potato as yams aren’t widely available at grocery stores throughout the U.S.
This recipe is written for fresh sweet potatoes. Canned varieties can differ in moisture and sweetness, especially those packed in syrup, so they may change the filling’s texture and flavor. Stick with fresh for the most predictable results.
More Sweet Potato Recipes to Try
If you enjoyed this recipe, please consider leaving a ⭐ star rating and let me know how it went in the 📝 comments below.

Marshmallow-Topped Sweet Potato Casserole
Ingredients
- 6 cups mashed sweet potatoes, about 4 large sweet potatoes
- ½ cup coconut sugar, or brown sugar
- ¼ cup unsalted butter, softened
- 1 teaspoon sea salt
- ½ teaspoon vanilla
- 2 cups miniature marshmallows
Instructions
- Heat oven to 400°F. Pierce sweet potatoes with a fork several times. Place sweet potatoes on baking sheet. Roast 1 hour or until tender. Let cool and remove skin from the sweet potatoes and discard.
- Place flesh into large bowl, mash with a fork or potato masher and measure 6 cups. Save any extra for another use. Reduce oven temperature to 375° F.6 cups mashed sweet potatoes
- Add sugar, softened butter, salt and vanilla to the sweet potatoes. Stir to combine. You can use a hand mixer or stand mixer for this if you'd like.½ cup coconut sugar, ¼ cup unsalted butter, 1 teaspoon sea salt, ½ teaspoon vanilla
- Transfer sweet potato mixture to a 9 x 9-inch baking dish coated with cooking spray. Use a spoon to make sure the mixture is evenly distributed. Top with marshmallows.2 cups miniature marshmallows
- Bake for 20-25 minutes or until marshmallows are golden. Serve warm.
Notes
- Boil sweet potatoes: If you prefer to boil them, peel and cube the potatoes, cover with water and simmer until tender. Drain, mash and use in the recipe.
- To store: Let the casserole cool, cover and refrigerate for 3 to 4 days. Reheat at 350°F until warm.
- To freeze: Bake without marshmallows, cool, cover tightly and freeze up to 3 months. Thaw overnight in the refrigerator, then follow the make-ahead reheating directions.
- Make ahead: Assemble up to 2 days ahead without marshmallows. Cover and refrigerate. In a refrigerator-to-oven-safe dish, heat covered at 375°F until hot throughout, then add marshmallows and bake uncovered until golden.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Like This Recipe? Rate & Comment Below!

















It was so easy to make. My boys and husband were skeptical because they usually don’t like sweet potatoes. But it was a hit. They came for second and thirds :). I was asked to add to the list of all our holidays meals !
Great recipe. I made it for Thanksgiving for a large crowd and it was a crowd pleaser, not a morsel left.
Ah yay! So happy to hear this recipe was a hit over Thanksgiving, Brigitte! Thanks so much for making it and coming back to leave a review. It means so much to me!
Made this for Thanksgiving and everyone absolutely loved it, especially me. Sweet potato casserole is always a highlight for me and I’m happy I found your page and tried this one out!
Yay!! This makes me so happy to hear. So thrilled this sweet potato casserole was a success, Lindsay. Thanks so much for the review!
We added pecans instead of marshmallows and a touch of baking powder to make the potatoes fluffy and it was deeeelicious! Thanks!
Ah yay! So happy to hear this sweet potato casserole was a success, Misty! Thanks so much for letting me know how it turned out. I really appreciate the feedback!
Soooo yummy! Made this today along with the healthy sweet potato casserole to decide which to make for thanksgiving. The kids LOVED this one! Perfect balance of sweet and savory and pretty easy to put together. Highly recommend this one!
I am making your Classic Sweet Potato Casserole for Thanksgiving along with your quinoa stuffing (will let you know!). I have made your Crunchy Asian Chopped Salad and Blueberry Corn Chicken Salad from your salad download and my family is raving!
Ahh yay, I love hearing that! Definitely let me know how the sweet potato casserole + stuffing turns out. 🙂
This was surprising easy and very tasty dish to make. Made it for the family as I had bought too many sweet potatoes last week and needed to use them. IT turned out perfect.
So glad this dish was a hit, Anita! Thanks for making it and for coming back to leave a comment + star rating. I appreciate it. 🙂