Southern Sweet Potato Casserole with Marshmallow Topping
This beloved Southern classic combines creamy, spiced sweet potato filling with a cloud-like marshmallow topping that browns to golden perfection. The dish balances warm spices—cinnamon, ginger, and nutmeg—with subtle vanilla and the richness of butter and eggs, creating a comforting texture that's part custard, part soufflé. Sweet potato casserole is a Thanksgiving and holiday table essential, though equally welcome at potlucks or family dinners year-round. What sets this version apart is the option to layer both pecan praline and marshmallows, letting you customize the topping to preference. The two-stage baking method ensures the filling stays creamy while the marshmallows toast to an ideal crispy-exterior, soft-interior finish. Perfect for cooks seeking a foolproof make-ahead side dish that impresses without fuss.
Ingredients
- 3 large sweet potatoes, cooked and mashed, for about 3 cups
- ½ cup unsalted butter
- ¾ cup granulated sugar
- kosher salt, pinch
- 2 large eggs, beaten
- ¼ cup half and half
- 1 teaspoon ground cinnamon
- 1 teaspoon ground ginger
- ¼ teaspoon ground nutmeg
- 1 teaspoon pure vanilla extract
- 3 cups mini marshmallows(optional)pecan praline toppingvariestoppingadds tree_nuts
removes marshmallow sweetness and texture
Full guide → - pecan praline topping, or substitute for marshmallows(optional)
Instructions
- 1
Preheat oven to 375 degrees F and butter a casserole dish.
- 2
Mash the cooked, cooled sweet potatoes until smooth.
- 3
Stir in butter, half the sugar, salt, half and half, cinnamon, ginger, nutmeg, and vanilla extract until well combined and taste.
- 4
Add remaining sugar as needed to reach desired sweetness.
- 5
Beat in the eggs with an electric mixer at medium speed until smooth.
- 6
Pour the mixture into the prepared casserole dish.
- 7
If using pecan topping, sprinkle over the entire surface; if using both toppings, apply pecans to the center and leave a border of sweet potato around the edges.
- 8
Cover and bake at 375 degrees F for about 30 minutes, until heated through.
- 9
Remove from oven, uncover, and spread marshmallows on top, covering entirely if using only marshmallows, or around the edges if combining with pecans in the center.
- 10
Bake uncovered for about 10 minutes longer until marshmallows are nicely browned.
Tips
Make the sweet potato mixture the day before and refrigerate it in the casserole dish. On serving day, add 5-10 minutes to the covered baking time since the filling starts cold. This allows marshmallows to toast beautifully without overbaking the filling.
For even browning of marshmallows, position the oven rack in the upper-middle position during the final 10-minute bake. Watch closely—marshmallows can brown quickly. If browning too fast, cover loosely with foil.
If your oven runs hot, rotate the dish halfway through the final baking step to ensure uniform marshmallow browning. Marshmallow size varies by brand; smaller ones toast faster than large ones.
Good to Know
Cover and refrigerate leftovers for up to 3 days. Reheat gently at 325 degrees F, covered, until warmed through—about 15-20 minutes. Marshmallow topping will soften on storage.
Prepare the sweet potato mixture through the egg-beating step and pour into the casserole dish up to 24 hours ahead. Refrigerate covered. Bake as directed, adding 5-10 minutes to the initial covered baking time. Add marshmallows after removing from oven for the first time, then bake uncovered as instructed.
Serve warm as a side dish at Thanksgiving, Christmas, Easter, or any holiday meal. Also suitable for potlucks, family dinners, or special brunches. Pairs well with roasted turkey, ham, or prime rib.
Common Mistakes
Do not skip cooling the cooked sweet potatoes before mashing to avoid curdling the eggs when added later.
Do not bake the marshmallows for longer than 10 minutes to avoid burning them completely—they brown quickly once exposed to direct heat.
Do not stir the filling after pouring into the dish and before baking to maintain the proper texture; gentle folding of eggs is sufficient.
Substitutions
Dairy-Free Swaps
General Alternatives
removes marshmallow sweetness and texture
Full guide →FAQ
Can I make this casserole ahead and freeze it?
Yes, freeze the unbaked casserole (before adding marshmallows) for up to 3 months, covered tightly. Thaw overnight in the refrigerator before baking, adding 10-15 minutes to the initial covered baking time. Add marshmallows after the first stage and bake uncovered as directed.
What if I don't have half and half?
Use heavy cream or whole milk in equal amounts. Heavy cream yields a richer casserole; whole milk produces a slightly lighter version. Evaporated milk also works well at the same ratio, adding subtle depth to flavor.
How do I prevent marshmallows from burning while the filling finishes cooking?
Add marshmallows only after the initial 30-minute covered bake, when the filling is already heated through. The short 10-minute uncovered bake at 375 degrees F is just enough to brown the tops. Watch closely during the final minutes to pull the dish out at peak browning.