If you have ever dreamed of a cozy, comforting dish that tastes like autumn on a plate, then this Sweet Potato Casserole with Pecans, Marshmallows, and Pumpkin Spice Recipe is absolutely for you. It brings together the natural sweetness and creaminess of mashed sweet potatoes with the warm, aromatic notes of pumpkin pie spice, all crowned with a crunchy pecan topping and gooey toasted marshmallows. This dish is the perfect centerpiece for holiday dinners or any time you want a bit of seasonal magic in your kitchen.

Ingredients You’ll Need
The beauty of this recipe lies in its straightforward, everyday ingredients that each play a special role in creating the perfect balance of flavors, textures, and colors. From the velvety sweet potatoes to the crunchy pecans and fluffy marshmallows, every component is essential to make this dish truly unforgettable.
- Sweet potatoes (3 ½ pounds, peeled and cut into large chunks): The creamy base of the casserole, packed with natural sweetness and vibrant color.
- Brown sugar (½ cup + ¼ cup packed): Adds a deep, caramel-like sweetness that perfectly complements the earthiness of the sweet potatoes and the pecans.
- Unsalted butter (¾ cup total, melted): Imparts richness and helps bind everything together while enhancing the nutty crust.
- Pumpkin pie spice (1 teaspoon): The warm spice blend that gives the casserole its signature fall flavor and cozy aroma.
- Vanilla extract (1 teaspoon): A subtle touch that brightens the sweet potato mixture and adds depth.
- Salt (½ teaspoon): Balances the sweetness and elevates all the flavors.
- Pecans (1 cup, chopped): Provide a satisfying crunch and nutty contrast in the topping.
- All-purpose flour (3 tablespoons): Helps bind the pecan topping so it stays crisp and golden after baking.
- Mini marshmallows (5 ounces): The final magical layer that toasts beautifully in the oven, adding gooey sweetness and delightful texture.
How to Make Sweet Potato Casserole with Pecans, Marshmallows, and Pumpkin Spice Recipe
Step 1: Prepare the Sweet Potato Layer
Start by boiling the peeled and chopped sweet potatoes until they are tender and easily pierced with a fork. This usually takes about 15 minutes. Once cooked, drain them well and mash until smooth and creamy. Then, stir in the brown sugar, melted butter, pumpkin pie spice, vanilla extract, and salt. This mixture should be perfectly balanced—sweet with a hint of spice and richness that will form the luscious base of your casserole.
Step 2: Assemble the Topping
In a separate bowl, combine the chopped pecans with melted butter, brown sugar, and all-purpose flour. This combination creates a textured, slightly crunchy topping that will contrast perfectly against the soft sweet potato layer. Sprinkle this mixture evenly over the prepared sweet potatoes, making sure every bite will deliver a little crunch.
Step 3: Add Marshmallows and Bake
Top the pecan layer with a generous handful of mini marshmallows. When baked at 350°F (175°C) for about 20 minutes, the marshmallows toast and melt into a golden, bubbly, and irresistible topping. Keep an eye on them toward the end so they don’t burn, but do let them achieve that perfect lightly browned color.
How to Serve Sweet Potato Casserole with Pecans, Marshmallows, and Pumpkin Spice Recipe

Garnishes
If you want to add a little extra flair, consider sprinkling a few additional chopped pecans or a pinch of extra pumpkin pie spice on top right after baking. This will enhance both the visual appeal and the aroma, making your presentation irresistible to guests sitting at the table.
Side Dishes
This casserole makes a fantastic companion to classic holiday mains like roasted turkey, glazed ham, or even a rich beef brisket. For a lighter spread, pair it with fresh green beans, a crisp salad, or sautéed Brussels sprouts to provide a lovely balance between sweet and savory on your plate.
Creative Ways to Present
To make this dish stand out, try baking and serving it in individual ramekins for a personalized touch. You can also sprinkle edible gold dust on the marshmallows or add a drizzle of caramel sauce just before serving for an extra layer of decadence that will wow your family and friends.
Make Ahead and Storage
Storing Leftovers
Leftover sweet potato casserole stores beautifully in an airtight container in the refrigerator for up to 3 days. The flavors actually develop further, making it taste even better the next day!
Freezing
This casserole freezes well if you want to prepare it in advance. Bake it as directed, cool completely, then wrap tightly with plastic wrap and aluminum foil before placing in the freezer. It can last up to 2 months frozen without losing its delicious texture and flavor.
Reheating
To reheat, thaw the casserole overnight in the refrigerator if frozen. Warm it in a 350°F (175°C) oven for about 15-20 minutes until heated through and the marshmallows regain their fluffiness. Avoid microwaving to maintain the perfect texture of the pecan topping.
FAQs
Can I substitute regular sugar for brown sugar in this recipe?
While brown sugar adds a richer flavor due to its molasses content, you can use regular granulated sugar if necessary. Your casserole will be slightly less deep in flavor but still delicious.
Is it okay to use frozen sweet potatoes?
Fresh sweet potatoes will always be ideal for the best texture and flavor, but if time is tight, cooked frozen sweet potatoes can work. Just be sure to thaw and drain any excess moisture before mashing.
Can I use other nuts instead of pecans?
Absolutely! Walnuts or almonds make great alternatives if pecans aren’t your favorite. Just chop them roughly and proceed as usual for the topping.
What if I don’t want to use marshmallows?
If marshmallows aren’t your thing, you can skip them and simply increase the pecan topping or sprinkle with shredded coconut for a different but equally tasty finish.
How spicy is the pumpkin pie spice in this casserole?
The pumpkin pie spice adds a warm, aromatic note rather than heat, with cinnamon, nutmeg, and cloves creating a cozy flavor profile that complements the sweetness without overpowering the dish.
Final Thoughts
This Sweet Potato Casserole with Pecans, Marshmallows, and Pumpkin Spice Recipe is more than just a side dish; it’s a celebration of autumn flavors and comforting textures all baked into one indulgent dish. Whether you’re serving it for a festive holiday feast or simply craving a rainy day treat, this casserole is sure to bring smiles and warm memories to your table. Give it a try—you’ll quickly understand why it’s a favorite that’s cherished year after year!
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Sweet Potato Casserole with Pecans, Marshmallows, and Pumpkin Spice Recipe
- Prep Time: 15 minutes
- Cook Time: 20 minutes
- Total Time: 35 minutes
- Yield: 10 servings
- Category: Side Dish
- Method: Baking
- Cuisine: American
Description
A classic and comforting Sweet Potato Casserole featuring a creamy mashed sweet potato base mixed with warm spices and brown sugar, topped with a crunchy pecan streusel and melted mini marshmallows, baked to golden perfection. Perfect as a side dish for holiday meals or any cozy dinner.
Ingredients
Sweet Potato Layer
- 3 ½ pounds sweet potatoes (peeled and cut into large chunks)
- ½ cup brown sugar
- ½ cup unsalted butter (melted)
- 1 teaspoon pumpkin pie spice
- 1 teaspoon vanilla extract
- ½ teaspoon salt
Pecan Topping
- 1 cup pecans (chopped)
- ¼ cup unsalted butter (melted)
- ¼ cup brown sugar (packed)
- 3 tablespoons all-purpose flour
Additional Topping
- 5 ounces mini marshmallows
Instructions
- Prepare Sweet Potatoes: Boil the peeled and chunked sweet potatoes in a large pot of water until they are tender and easily pierced with a fork, about 15-20 minutes. Drain well to remove excess water.
- Mash and Mix: Transfer the drained sweet potatoes to a large bowl and mash them until smooth. Stir in the brown sugar, melted butter, pumpkin pie spice, vanilla extract, and salt until the mixture is well combined and creamy.
- Assemble Sweet Potato Layer: Pour the sweet potato mixture evenly into a baking dish, spreading it out smoothly to form the base layer of the casserole.
- Make Pecan Topping: In a separate bowl, combine the chopped pecans, melted butter, brown sugar, and all-purpose flour. Mix the ingredients together until they form a crumbly topping mixture.
- Top Sweet Potatoes: Sprinkle the pecan topping evenly over the sweet potato layer in the baking dish.
- Add Marshmallows: Evenly distribute the mini marshmallows over the pecan topping for a sweet, gooey finish.
- Bake: Preheat your oven to 350°F (175°C). Place the casserole on the middle rack and bake for 20 minutes, or until the marshmallows are golden brown and the filling is heated through.
Notes
- For a smoother texture, you can use a hand mixer to mash the sweet potatoes.
- Make sure to drain the sweet potatoes thoroughly to avoid a watery casserole.
- Toast the pecans lightly if you prefer a deeper nutty flavor before mixing with the topping ingredients.
- Keep an eye on the marshmallows during baking to prevent burning—cover with foil if they brown too quickly.
- This dish can be prepared a day ahead and baked just before serving for convenience.

