Sweet Potato Casserole with Marshmallows (Best Holiday Side)

This simple dry-out trick makes your sweet potato casserole thicker, creamier, and unbelievably smooth — no more watery casseroles.

This warm, cozy sweet potato casserole with marshmallows is the kind of holiday side dish everyone looks forward to. The filling is silky, lightly sweet, and packed with fall flavor, while the marshmallow topping turns golden and gooey in the oven. If you’re planning a full Thanksgiving spread, this pairs beautifully with classics like easy holiday side dishes.

The secret? After boiling, let the sweet potatoes dry in the warm pot for 2–3 minutes — this removes excess moisture and gives the casserole a rich, creamy texture that never turns watery.

Why You’ll Love It

Family favorite: Sweet, fluffy, and nostalgic.
Perfect texture: Creamy base with a gooey toasted top.
Holiday staple: Makes any table feel festive.
Flexible: You can also serve it alongside classic green bean casserole or savory sweet potato dishes.

Ingredients

4 large sweet potatoes (about 3 lb), peeled and cubed
1/2 cup unsalted butter, melted
1/3 cup packed brown sugar
1/4 cup milk
2 large eggs
1 tsp vanilla extract
1/2 tsp ground cinnamon
1/4 tsp nutmeg
1/2 tsp salt
3 cups mini marshmallows

Close-up of toasted marshmallows on sweet potato casserole

Instructions

Preheat oven to 350°F. Grease a 9×13-inch baking dish and set aside.
Add the sweet potatoes to a large pot and cover with water. Bring to a boil and cook 15–20 minutes, until fork-tender.
Return the drained sweet potatoes to the warm pot and let them sit over low heat for 2–3 minutes, stirring occasionally.
Mash until smooth (the dry-out step makes the mash extra creamy and thick).For extra creaminess, you can use a hand mixer on low speed.
Stir in melted butter, brown sugar, milk, eggs, vanilla, cinnamon, nutmeg, and salt. Mix until the filling is smooth.
Transfer mixture to the baking dish and spread evenly.
Bake for 20 minutes, then remove from the oven and sprinkle marshmallows evenly over the top.
Return to the oven for 10–15 minutes, until the marshmallows turn golden brown and soft.

Tips & Variations

Dry the sweet potatoes in the warm pot for 2–3 minutes before mashing — this prevents watery casseroles and gives a rich, velvety texture.
Swap mini marshmallows for large ones if you prefer bigger toasted pockets of sweetness.
Add a pecan crumble for a crunchy twist—brown sugar, flour, butter, and chopped pecans work perfectly.
For extra flavor, stir in 1–2 tbsp maple syrup.
Want a savory contrast? Serve with creamy Parmesan mashed sweet potatoes alongside your meal.

Substitutions

Dairy-free: Use plant-based butter and oat milk.
Egg-free: Replace eggs with 3 tbsp melted butter.
Lower sugar: Reduce brown sugar to 2 tbsp.

Serving Suggestions

This casserole shines on any holiday table. Serve it next to turkey, ham, or a vegetarian centerpiece. It’s especially good with dishes that offer a savory balance, such as herb-roasted meats or creamy soups.

Storage & Reheating

Refrigerate: Store leftovers in an airtight container for up to 4 days.
Reheat: Warm in a 300°F oven for 10–15 minutes until the marshmallows soften again.
Make-ahead: Assemble the casserole without the marshmallows, refrigerate up to 24 hours, then add the topping just before baking.

FAQs

Can I use canned sweet potatoes?

Yes—drain them well and reduce added sugar slightly since canned versions can be naturally sweeter.

Can I prepare this in advance?

Absolutely. Prepare the base, refrigerate, and add marshmallows just before baking for the best texture.

Can I freeze sweet potato casserole?

Freeze the base only (without marshmallows) for up to 2 months. Thaw in the fridge overnight, then add the topping and bake.

More to Try

Conclusion

This sweet potato casserole with marshmallows delivers everything you want in a holiday dish—warmth, sweetness, and pure comfort. It’s easy to prepare, always crowd-pleasing, and perfect for Thanksgiving or any cozy meal at home.