If there’s one dessert side dish that feels like pure comfort, it’s sweet potato casserole with marshmallows. This iconic American classic blends smooth, creamy sweet potatoes with a crunchy, buttery topping and gooey toasted marshmallows. It’s a holiday favorite for a reason — it’s easy to make, crowd-pleasing, and instantly nostalgic. Whether you’re serving it at Thanksgiving, Christmas, or just a cozy family dinner, this recipe is guaranteed to become a new favorite.

What makes this casserole special is its balance of flavors. The sweet potatoes bring natural sweetness, while butter, brown sugar, and warm spices create a rich, dessert-like base. The marshmallow topping adds that signature toasted sweetness and soft, cloud-like texture. But the best part? You can make this casserole ahead of time, then bake it when you’re ready to serve.

If you’re looking for a recipe that tastes like holiday magic but is simple enough for weeknight cooking, this Easy Sweet Potato Casserole with Marshmallows is your answer.

Why This Sweet Potato Casserole Works

1. The Sweet Potato Base Is Creamy, Not Runny

The secret to a perfect casserole is cooking the sweet potatoes until they’re tender enough to mash smoothly, but not so watery that the casserole becomes soupy. This recipe uses cooked sweet potatoes mashed with butter, brown sugar, and a touch of cinnamon and vanilla for a creamy texture that holds up well during baking.

2. A Balanced Sweetness

Sweet potatoes are naturally sweet, so the key is adding just enough sugar to enhance the flavor without overpowering it. Brown sugar adds a caramel-like depth, while marshmallows add a bright sweetness that contrasts beautifully with the warm spices.

3. The Marshmallow Topping Is Toasted Perfectly

The marshmallow layer should be golden brown on top and soft underneath. If your oven is too hot or the marshmallows are too close to the heat, they can burn quickly. This recipe uses a two-step baking method: bake the casserole first, then add marshmallows and broil just until toasted.

Ingredients

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

Optional Topping (for extra crunch):

1/2 cup chopped pecans
1/2 cup brown sugar
1/4 cup melted butter
1/2 cup all-purpose flour

Instructions

Preheat the oven to 350°F (175°C). Grease a 9×13-inch baking dish or casserole dish.
Cook the sweet potatoes: Peel and cube the sweet potatoes. Boil them in a large pot until fork-tender, about 15–20 minutes. Drain well.
Mash the sweet potatoes: Add the cooked sweet potatoes to a large bowl and mash until smooth.
Mix the base: Add melted butter, brown sugar, milk, eggs, vanilla, cinnamon, nutmeg, and salt. Mix until smooth and creamy.
Spread into the baking dish: Pour the sweet potato mixture into the prepared baking dish and spread evenly.
Bake the casserole for 25–30 minutes, until heated through and slightly set.
Add the marshmallows: Remove the casserole from the oven. Sprinkle the mini marshmallows evenly over the top.
Broil until golden: Turn the oven to broil. Place the casserole under the broiler for 1–3 minutes, watching carefully. Toast until marshmallows are golden brown and puffed.
Serve warm: Let the casserole cool for 5 minutes, then serve warm.

Tips for the Best Sweet Potato Casserole

1. Use Real Sweet Potatoes, Not Canned

Canned sweet potatoes are convenient, but they’re often too watery and can make the casserole too soft. Fresh sweet potatoes provide the best texture and flavor.

2. Don’t Skip the Eggs

Eggs help the casserole hold its shape and prevent it from becoming too runny. If you want a richer texture, add an extra egg.

3. Mash Smooth for a Dessert-Like Texture

Use a hand mixer or potato masher to get a smooth, creamy texture. Small chunks are okay, but the best casseroles are silky.

4. Use Mini Marshmallows

Mini marshmallows toast evenly and create a perfect marshmallow crust. Large marshmallows can melt unevenly.

5. Watch the Broiler Closely

Broilers can burn marshmallows fast. Stay close and broil in 30-second intervals until golden.

Variations to Try

Pecan Streusel Topping

Mix 1/2 cup chopped pecans, 1/2 cup brown sugar, 1/2 cup flour, and 1/4 cup melted butter. Sprinkle over the casserole before baking. Add marshmallows at the end.

Coconut Marshmallow Topping

Add shredded coconut to the marshmallow topping for a tropical twist.

Spiced Orange Sweet Potato Casserole

Add 1 tablespoon orange zest and 1 tablespoon orange juice for a bright citrus flavor.

Savory Sweet Potato Casserole

Reduce the sugar and omit marshmallows. Add shredded cheddar cheese and top with crispy onions for a savory side dish.

Serving Suggestions

Sweet potato casserole is a perfect side dish for:

Thanksgiving turkey
Holiday dinners
Roasted chicken or pork
Comfort food nights
Potlucks and family gatherings

Pair it with green beans, roasted carrots, or a fresh salad to balance the sweetness.

Fun Facts & Cultural Context

Sweet potato casserole is believed to have become popular in the United States in the early 20th century. It was originally a simpler dish, made with mashed sweet potatoes and butter. The marshmallow topping became popular in the 1950s when American cooks began experimenting with sweeter and more decorative holiday dishes.

Today, sweet potato casserole is a Thanksgiving staple, symbolizing comfort, tradition, and the warmth of family gatherings. Its sweet, creamy texture and toasted marshmallow topping make it feel like a dessert, even though it’s served as a side dish.

Storage & Reheating

To Store

Cover leftovers tightly and refrigerate for up to 3–4 days.

To Reheat

Warm in the oven at 350°F (175°C) for 10–15 minutes. Add fresh marshmallows on top and broil for 1–2 minutes for a toasted finish.

Why You’ll Love This Recipe

This recipe is simple, reliable, and delicious. It’s a great way to bring a classic holiday flavor to your table without complicated steps. Whether you’re hosting a big dinner or just want a comforting treat, this sweet potato casserole delivers on taste, texture, and nostalgia.