Sweet Potato Casserole

Sweet potato casserole with marshmallows is an iconic part of many a Thanksgiving spread. My grandma used to serve it in a 1970s-era Pyrex dish, which had a burnt orange color that matched the potatoes. Her casserole was famous for its ratio of one part sweet potato to three or four parts marshmallows.

This recipe has a more balanced ratio, with a thick layer of smooth, lightly spiced sweet potatoes and a delicious scattering of toasted marshmallows. Because the marshmallows are added at the end and baked for 5 to 10 minutes, they get nice and browned on the outside and perfectly gooey inside. In other words, they’re absolute bliss!

Because of their seasonality, sweet potatoes generally make for good fall fare. Serve this classic casserole with other Thanksgiving sides or as a special treat with a Sunday dinner. Be sure to choose the best marshmallows when making this dish; the jumbo ones with a hint of vanilla make all the difference.

Sweet Potato Casserole Ingredients

• Sweet potatoes: Look for large sweet potatoes with firm, unblemished skin. Avoid potatoes with bruises or cracks. Sweet potatoes differ from yams (which have white flesh), so double check the produce before buying.
• Milk: Milk thins the mashed sweet potatoes, giving them a smoother texture. We call for 2% here, but you can use any milk you like, including nondairy milks (just make sure it doesn’t have extra flavors or sweeteners).
• Brown sugar: With its molasses-tinged richness, brown sugar adds a caramel flavor to the casserole.
• Butter: A generous dollop of softened butter mixes with the milk to thin and enrich the mashed sweet potatoes.
• Egg: To make this dish a casserole instead of just plain-old mashed sweet potatoes, use eggs to ensure an even bake with a slightly puffy, stable base.
• Spices: Cinnamon, allspice, nutmeg and salt give this potato casserole the tempting flavors associated with classic fall desserts.
• Vanilla extract: Although sweet potato casserole is more side dish than dessert, it still uses vanilla extract to enhance the flavors—just like a sweet potato pie!
• Marshmallows: The toasty-on-top, gooey-inside marshmallow topping is the signature cap of sweet potato casserole. If you’re making sweet potato casserole for a sentimental crowd, skip it at your own peril!

Directions

Step 1: Cook the sweet potatoes

Place the sweet potatoes in a large saucepan and cover them with water. Bring the water to a boil, then reduce the heat. Cover the pot and cook until the potatoes are tender when pierced with a knife through the thickest part of the potato. This will take about 15 to 20 minutes. Drain the potatoes.

Editor’s Tip: Don’t rush cooking the potatoes, as undercooked sweet potatoes are hard to mash.

Step 2: Mash and season the sweet potatoes

Transfer the sweet potatoes to a large bowl and mash them until they’re smooth. Add the milk, brown sugar, butter, egg, cinnamon, vanilla, allspice, salt and nutmeg to the bowl. Beat them together until they’re smooth and evenly mixed.

Editor’s Tip: You can use a potato masher, fork or wooden spoon to mash the sweet potatoes.

Step 3: Bake the sweet potato mixture

Transfer the mixture to a greased shallow 2-1/2-quart baking dish. Bake the casserole, uncovered, at 350°F until it’s heated through, about 40 to 45 minutes.

Step 3: Add marshmallows and bake the casserole

Remove the dish from the oven and arrange the marshmallows across the top of the casserole. Return it to the oven and bake just until marshmallows begin to puff and brown, about 5 to 10 minutes longer.

Editor’s Tip: Marshmallows go from nicely browned to scorched quite quickly, so keep a close eye here; this isn’t the time to wander away from the oven.

Sweet Potato Casserole Variations

• Add a struesel topping: A crunchy, struesel-style topping is a nice contrast to the smooth sweet potatoes. To make one, omit the marshmallows and reduce the brown sugar in the potato mixture to 1/4 cup. For the topping, combine 3/4 cup of all-purpose flour, 3/4 cup of packed brown sugar, 3/4 cup of chopped pecans and 1/2 cup of melted butter in a small bowl. Sprinkle the struesel over the mashed sweet potatoes. Bake the casserole at 350° until the topping is browned, 50 to 55 minutes.
• Play with other toppings: Instead of marshmallows, scatter nuts across the top of the casserole (we especially like pecans or walnuts). Crumbled oatmeal cookies or gingersnaps are good too.
• Make a faux struesel: Mix 1/4 cup of melted butter, 1/2 cup of brown sugar and 1 cup of cornflakes or crushed-up butter crackers for a speedy crunchy topping.
• Make individual casseroles: You can cook sweet potato casserole in individual-sized ramekins rather than in the large pan. Reduce the baking time by about half, as the smaller pans will heat quickly.

How to Store Sweet Potato Casserole

Keep leftover sweet potato casserole in the refrigerator, tightly covered with storage wrap or foil. You can also transfer leftovers to an airtight container, though it can tough to keep the marshmallows neatly on top when doing so.

How long does sweet potato casserole last?

In the refrigerator, sweet potato casserole will keep well for three to four days. The marshmallows will get softer as they’re chilled.

Can you freeze sweet potato casserole?

Yes, like most casserole recipes, sweet potato casserole freezes well—except for the marshmallow topping. To get around this, prep the casserole through Step 3, then, instead of baking it, cover and freeze it for up to three months. Defrost it in the refrigerator, then proceed with the recipe from Step 4.

How do you reheat sweet potato casserole?

To crisp the marshmallows back up, we like to reheat this casserole in the oven or toaster oven, but you can also heat it up in a microwave.

Can you make sweet potato casserole ahead of time?

You can make the casserole ahead, but the marshmallow topping really does taste best freshly baked. We suggest making the potato mixture in advance, then wrapping and storing it in the refrigerator until ready to bake (you can do this up to three days ahead of time). Bring it to room temperature, then proceed with the recipe from Step 4.

Sweet Potato Casserole Tips

What else can you serve with sweet potato casserole?

Sweet potato casserole is a classic Thanksgiving dish, and thrives alongside favorites like roast turkey, corn, green bean casserole and mashed potatoes. It also makes a delightful Christmas casserole. The sweet side dish is too cozy to reserve just for holidays, though. Consider making Sunday night’s roast chicken feel extra festive by serving it with sweet potato casserole (and perhaps a green salad to keep things slightly healthy). Or, bring this casserole to literally any potluck; whether a formal church gathering or a raucous game day event, we bet it’ll be the first pan cleaned out.

How else can I cook the sweet potatoes faster?

There are so many ways to cook sweet potatoes. Boiling the potatoes whole is simple and cooks them nice and evenly, but you can speed up the process by cutting the sweet potatoes into chunks before boiling them.

You can also microwave the sweet potatoes. We suggest slicing them into medium-sized pieces. Arrange them in a microwave-safe container with a lid and add water about halfway up the side. Cook the potatoes on high for 10 minutes, then check them for doneness. (Be very careful when removing the container and lid, as the steam will be very hot.)