This Sweet Potato Casserole with Pecans and Marshmallows is the best of both worlds: a crunchy, buttery pecan topping and a gooey, golden marshmallow drizzle. Roasted sweet potatoes are whipped until silky smooth and sweetened just enough, then topped with a crunchy streusel and finished with a warm, creamy marshmallow topping. It's a beloved Thanksgiving and Christmas side dish with a delicious twist!
Why You'll Love This Recipe
- Two toppings in one! Can't decide between pecans or marshmallows? You don't have to.
- Roasted sweet potatoes have a deep, caramelized flavor.
- Perfect texture combo: Creamy base, crunchy topping, soft marshmallow finish.
- Make-ahead friendly: for stress-free holidays.
- Crowd favorite: this dish disappears fast every time!
The pecan topping bakes with the casserole for crunch. The marshmallow drizzle goes on after baking so it stays soft. If you prefer the classic toasted look, skip the drizzle and add mini marshmallows in the last 5 minutes instead.
Tips for Success
I've made sweet potato casserole with both boiled and roasted sweet potatoes, and I prefer roasting because it brings out their natural sweetness without adding extra moisture. I like using a hand mixer for the sweet potatoes because it gives the filling a lighter, smoother texture than mashing them by hand. I've found that the pecan topping and marshmallow drizzle add plenty of sweetness, so I don't need to make the sweet potato filling overly sweet.
- Roasting vs. boiling: Roasting concentrates flavor and keeps potatoes from becoming watery.
- Don't skip the salt: It balances the sweetness and enhances the flavor.
- Use room-temperature ingredients for easier blending.
- To save time, you can roast and mash the sweet potatoes up to 3 days ahead.
Make Ahead Instructions
- Prepare the sweet potato filling and spread into the baking dish.
- Mix the pecan topping and store separately in an airtight container at room temp.
- Refrigerate the sweet potato base up to 3 days.
- When ready to bake, bring to room temp, add the pecan topping, and bake as directed.
- Prepare and drizzle the marshmallow topping just before serving.
- You can roast and mash the potatoes up to 3 days ahead. Store the pecan topping separately at room temperature. On the day of, add the topping and bake. Make the drizzle at the last minute. Leftovers reheat well in a 350°F oven for 15-20 minutes (add a splash of milk if the base looks dry).
Frequently Asked Questions
Can I use canned sweet potatoes?
Fresh roasted sweet potatoes are best for texture and flavor, but canned sweet potatoes (drained and mashed) can work in a pinch.
What size baking dish should I use?
A 9x13-inch dish or 2-quart baking dish works great for this recipe.
Can I use mini marshmallows instead of a drizzle?
Yes! Simply sprinkle them on top during the last 5 minutes of baking instead of using the melted drizzle.
Can I make it nut-free?
Absolutely. Just leave off the pecans or substitute with oats or crushed pretzels for crunch.
Can I roast the sweet potatoes in an air fryer?
Yes-375-400°F until soft, then proceed with the recipe.
How far ahead can I assemble it?
Up to 3 days for the base; add the pecan topping and bake the day of.
If you're building out your holiday menu, I've got a few more showstoppers! For a classic appetizer that never fails to impress, try these Oysters Rockefeller - they're incredible and always disappear fast. And Beef Wellington Bites are elegant and bite-sized.
For the main course, these Braised Beef Short Ribs are simmered in red wine and garlic, and they're a very popular recipe on this site. A couple of other popular recipes are this Boneless Prime Rib with a Garlic-Herb Crust or a this Rib Roast with a Wet Rub - both are very simple to make and practically fool-proof! And if you're going the traditional route, don't miss my guide on How to Cook a Spiral Ham, complete with a sweet and savory ham glaze recipe that's holiday magic.
Sweet Potato Casserole with Marshmallow Pecan Topping
This sweet potato casserole recipe is sprinkled with a delicious marshmallow pecan topping for crunchy and soft contrast. It's a traditional Christmas AND Thanksgiving side dish at our dinner table.
Ingredients
For the sweet potatoes
- 5 medium sweet potatoes (about 2½–3 pounds)
- 1–2 teaspoons vegetable or canola oil
- ½ cup granulated sugar
- 2 large eggs, beaten
- 1 (5-ounce) can evaporated milk
- ¼ cup (½ stick) unsalted butter, softened
- 1 teaspoon vanilla extract
- ½ teaspoon salt
For the Pecan Topping
- ½ cup all-purpose flour
- ½ cup packed light brown sugar
- ¼ cup (½ stick) unsalted butter, softened
- 1 cup pecans, chopped
For the Marshmallow Drizzle
- 2 tablespoons unsalted butter
- 10 regular-sized marshmallows
Instructions
- Preheat the oven to 400°F.
- Rub each sweet potato with a small amount of oil, pierce several times with a fork, and place on a foil-lined baking sheet. Roast for about 1 hour, or until soft (time varies by size). Remove from the oven and let cool enough to handle.
- Remove the skins and discard. Place the potatoes in a medium bowl and add the sugar, eggs, evaporated milk, butter, vanilla, and salt. Whip with a hand mixer until smooth and fluffy, then spread evenly into a greased baking dish.
- For the topping, mix the flour and brown sugar in a small bowl. Cut in the butter with a fork until pea-sized clumps form, then stir in the pecans. Spread the topping evenly over the sweet potato mixture.
Bake at 350°F for 30 minutes, or until heated through and the topping is lightly browned.
Melt the marshmallows and butter in a saucepan over low heat until smooth. Carefully pour the hot mixture into a resealable plastic bag coated with cooking spray inside (the mixture will be very hot—use oven mitts or a hot pad). Snip one corner and drizzle over the pecan topping. - Serve immediately.
Notes
- Piercing the potatoes lets steam escape while they roast.
- Instead of peeling, you can slice each potato in half and scoop out the flesh with a large spoon.
Nutrition Information:
Yield: 12 Serving Size: 1Amount Per Serving: Calories: 332Total Fat: 19gSaturated Fat: 8gTrans Fat: 0gUnsaturated Fat: 10gCholesterol: 60mgSodium: 217mgCarbohydrates: 38gFiber: 3gSugar: 24gProtein: 5g
This data was provided and calculated by Nutritionix.
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Raj says
Very nice & healthy recipe for potato casserole. I like.
Olivia says
Excited to try it. I love sweet potatoe. & marshmallow- but was always afraid try this!!
Jenny N says
I usually don't let sweet potato casseroles cross my eyes. But, I must say I would like to make this because it looks so good! I must make this!
Kristy Bernardo says
Thanks so much, Jenny! Cheers 🙂
John@Kitchen Riffs says
We usually do roast sweet potatoes for Thanksgiving, but every now and again we'll do a sweet casserole like this. This is an outstanding recipe! Loads of flavor, and much more sensible than so many recipes out there. Really good dish -- thanks. And Happy Thanksgiving!
Amy (Savory Moments) says
I love the look and sound of this casserole! It looks so good and the toppings take it over the top. Thanks for the Buffalo shout-out! We are just north of the city so we missed the bulk of it, but a lot of our family's houses and cars have been buried!
Kristy Bernardo says
Glad to hear that you and your family are safe, Amy. Hopefully the cars and houses have been dug out by now, yikes! Cheers and Happy Thanksgiving 🙂