Marshmallow Sweet Potato Casserole

Sweet potatoes are one of those ingredients I always have on hand during fall and winter. They’re cheap, they last forever in my pantry, and my kids actually eat them without complaining. But let’s be honest – regular baked sweet potatoes can get a little boring after a while.

That’s where this easy sweet potato casserole comes in. It takes those simple sweet potatoes and turns them into something that feels special enough for Thanksgiving dinner but simple enough for a random Tuesday night. I love that I can prep most of it ahead of time while I’m already in the kitchen making other dishes.

The best part? It works as either a side dish or dessert. My family can never decide which it is, and honestly, I don’t care as long as they’re eating it. Sometimes I’ll make two – one with marshmallows for the kids and one with a crunchy pecan topping for the adults.

What Kind of Sweet Potatoes Should I Use?

For this recipe, you can absolutely use canned yams like the recipe calls for – they’re convenient and work great for casseroles. If you want to use fresh sweet potatoes instead, go for the orange-fleshed varieties like Beauregard or Centennial, which have that classic sweet, creamy texture we all love in casseroles. You’ll need to bake or boil about 3-4 large sweet potatoes until they’re fork-tender, then mash them up before adding to your other ingredients. Whether you choose canned or fresh, make sure to drain any excess liquid so your casserole doesn’t turn out too watery.

Options for Substitutions

This sweet potato casserole is pretty forgiving when it comes to swaps and substitutions:

• Canned yams: You can absolutely use fresh sweet potatoes instead! You’ll need about 3 pounds – just bake them at 400°F for 45-60 minutes until tender, then peel and mash. Fresh sweet potatoes might be a bit less sweet, so taste and add a tablespoon or two more sugar if needed.
• Pecans: Don’t have pecans? Walnuts, chopped almonds, or even crushed graham crackers work great in the topping. You can also skip the nuts entirely if you have allergies.
• Milk: Any milk you have on hand works – whole milk, 2%, or even heavy cream for extra richness. Non-dairy options like almond or oat milk work too.
• Brown sugar: If you’re out of brown sugar, mix 3/4 cup white sugar with 2 tablespoons molasses, or just use all white sugar for a slightly less complex flavor.
• Marshmallows: While marshmallows are classic, you can skip them for a less sweet version, or try a streusel topping made with extra flour, butter, and brown sugar mixed together.
• Vanilla: Vanilla extract can be swapped with almond extract (use half the amount) or a pinch of cinnamon and nutmeg for warm spice notes.

Watch Out for These Mistakes While Baking

The biggest mistake people make with sweet potato casserole is not draining the canned yams properly, which leads to a watery, runny base that won’t set up nicely – pat them dry with paper towels and mash them well to remove excess moisture.

Another common error is adding the marshmallows too early, causing them to burn or disappear completely into the casserole – wait until the last 5-10 minutes of baking to add them so they get golden and toasted on top.

Don’t skip letting the casserole cool for at least 15 minutes after baking, as this resting time helps everything firm up and makes serving much cleaner.

For the crunchiest pecan topping, make sure your butter is completely melted and evenly mixed with the flour and brown sugar before sprinkling it over the sweet potato base.

What to Serve With Sweet Potato Casserole?

This sweet potato casserole is perfect alongside your Thanksgiving turkey or holiday ham, but it’s honestly good enough to be dessert! I love serving it with classic sides like green bean casserole, stuffing, and cranberry sauce for the full holiday spread. If you’re making it for a regular dinner, it pairs really well with roasted chicken or pork chops since the sweetness balances out savory main dishes nicely. Don’t forget to save room though – with all those marshmallows and pecans on top, this casserole is pretty rich and filling on its own!

Storage Instructions

Keep Fresh: This sweet potato casserole tastes amazing for days! Store it covered in the fridge for up to 4 days. I actually think it gets even better after sitting overnight because all those flavors have time to meld together.

Freeze: You can totally make this ahead and freeze it! Wrap the whole casserole tightly in plastic wrap and foil, and it’ll keep in the freezer for up to 3 months. Just remember to add the marshmallows after you thaw and reheat it, not before freezing.

Warm Up: To reheat, cover with foil and pop it in a 350°F oven for about 20-25 minutes until heated through. If you’re adding fresh marshmallows, remove the foil for the last 5 minutes to get them golden and toasty on top.

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 2500-2800
• Protein: 20-25 g
• Fat: 110-125 g
• Carbohydrates: 370-410 g

Ingredients

For the sweet potato base:

• 1 can (40 oz) yams, bruce’s brand preferred
• 1/3 cup butter
• 3/4 cup granulated sugar
• 1/4 cup milk
• 2 eggs
• 1 tsp vanilla extract

For the pecan topping:

• 1 cup pecan pieces
• 3/4 cup packed brown sugar
• 1/3 cup all-purpose flour
• 1/3 cup unsalted butter, melted

For the optional topping:

• 1 1/2 cups mini marshmallows (optional, add during last 5 minutes of baking)

Step 1: Prepare the Sweet Potatoes

• 1 can (40 oz) yams, Bruce’s brand preferred
• butter (for greasing pan)

Preheat your oven to 350°F (175°C).

Grease an 8×8 inch baking dish with some butter to prevent sticking.

In a medium saucepan, add the canned yams along with their liquid and bring to a boil.

Once boiling, reduce the heat and simmer until the sweet potatoes are fork-tender.

Drain the sweet potatoes and transfer them to a large bowl.

Step 2: Mash and Mix Sweet Potato Filling

• mashed sweet potatoes from Step 1
• 3/4 cup granulated sugar
• 1/3 cup butter
• 1/4 cup milk
• 2 eggs
• 1 tsp vanilla extract

Mash the drained sweet potatoes until smooth.

Add granulated sugar, butter, milk, eggs, and vanilla extract to the bowl.

Mix well until the ingredients are fully incorporated and the mixture is smooth and creamy.

This makes for a wonderfully silky filling—I like to mash until almost no lumps remain.

Step 3: Assemble the Casserole

• sweet potato filling from Step 2

Spread the sweet potato mixture evenly into the prepared, greased baking dish.

Set aside while you prepare the pecan topping.

Step 4: Make the Pecan Topping

• 1 cup pecan pieces
• 3/4 cup packed brown sugar
• 1/3 cup all-purpose flour
• 1/3 cup unsalted butter, melted

In a separate bowl, combine pecan pieces, packed brown sugar, all-purpose flour, and melted unsalted butter.

Mix well until the topping is evenly moistened and crumbly.

Step 5: Bake the Casserole

• pecan topping from Step 4
• mini marshmallows (optional, 1 1/2 cups)

Sprinkle the pecan topping evenly over the sweet potato mixture in the baking dish.

Bake in the preheated oven for 45 minutes, or until the topping is golden brown and the filling is set.

For a sweet finishing touch, I like to add mini marshmallows during the last 5 minutes of baking—just sprinkle them on top and let them get toasty.

Step 6: Cool and Serve

Let the casserole cool for at least 15 minutes before serving.

This allows the filling to set and makes it easier to cut and serve.

Enjoy!

Marshmallow Sweet Potato Casserole

Delicious Marshmallow Sweet Potato Casserole recipe with step-by-step instructions.

Print Recipe Pin Recipe

Prep Time 20 minutes mins

Cook Time 42 minutes mins

Total Time 1 hour hr 2 minutes mins

Servings 4

Calories 2650 kcal

Ingredients

  

For the sweet potato base:

• 1 can (40 oz) yams, Bruce's brand preferred
• 1/3 cup butter
• 3/4 cup granulated sugar
• 1/4 cup milk
• 2 eggs
• 1 tsp vanilla extract

For the pecan topping:

• 1 cup pecan pieces
• 3/4 cup packed brown sugar
• 1/3 cup all-purpose flour
• 1/3 cup unsalted butter, melted

For the optional topping:

• 1 1/2 cups mini marshmallows (optional, add during last 5 minutes of baking)

Instructions

 

• Preheat your oven to 350°F (175°C). Grease an 8x8 inch baking dish with some butter to prevent sticking. In a medium saucepan, add the canned yams along with their liquid and bring to a boil. Once boiling, reduce the heat and simmer until the sweet potatoes are fork-tender. Drain the sweet potatoes and transfer them to a large bowl.
• Mash the drained sweet potatoes until smooth. Add granulated sugar, butter, milk, eggs, and vanilla extract to the bowl. Mix well until the ingredients are fully incorporated and the mixture is smooth and creamy. This makes for a wonderfully silky filling—I like to mash until almost no lumps remain.
• Spread the sweet potato mixture evenly into the prepared, greased baking dish. Set aside while you prepare the pecan topping.
• In a separate bowl, combine pecan pieces, packed brown sugar, all-purpose flour, and melted unsalted butter. Mix well until the topping is evenly moistened and crumbly.
• Sprinkle the pecan topping evenly over the sweet potato mixture in the baking dish. Bake in the preheated oven for 45 minutes, or until the topping is golden brown and the filling is set. For a sweet finishing touch, I like to add mini marshmallows during the last 5 minutes of baking—just sprinkle them on top and let them get toasty.
• Let the casserole cool for at least 15 minutes before serving. This allows the filling to set and makes it easier to cut and serve. Enjoy!