Sweet Potato Casserole with Marshmallows

Sweet potato casserole with marshmallows is one of those holiday dishes that sparks intense debates about whether it's a side dish or dessert. You roast sweet potatoes until they're soft, mash them with butter, maple syrup, and cinnamon, spread everything in a baking dish, cover the top with mini marshmallows, and bake until those marshmallows get golden and toasted. The whole thing is ridiculously sweet and probably has no business being called a vegetable side, but it shows up on every Thanksgiving table anyway because tradition demands it.

My uncle Jim claims he doesn't like sweet foods and refuses dessert, but every single Thanksgiving, I watch him go back for seconds of this sweet potato casserole, piling it on his plate next to the turkey like it's a normal savory side dish. Now it's become this running joke where we all wait to see how much he'll eat before someone mentions the sugar content and he pretends to be offended.

Master Your Ingredients

• Sweet potatoes: Five to six large ones (Russet variety, do not use yams) for a 9x13 inch baking dish.
• Maple syrup: A third of a cup adds sweetness and distinctive maple flavor.
• Butter: One full stick, melted into the mashed sweet potatoes for richness and creamy texture.
• Ground cinnamon: One tablespoon brings warmth and spice.
• Mini marshmallows: One 10-ounce bag for the classic toasted topping.
• Salt: Just a pinch to balance all the sweetness and enhance the potato flavor.

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Making This Casserole (Holiday Prep)

Roasting the potatoes:

Preheat oven to 400 degrees Fahrenheit. Scrub potatoes, pat dry, and place on a parchment-lined baking sheet (do not peel yet). **Roast for 50 to 75 minutes** until easily pierced with a fork.

Mashing the filling:

Let potatoes cool slightly (10-15 minutes). Peel off the skins and place the flesh in a large mixing bowl. Add maple syrup, melted butter, cinnamon, and salt. Mash to your preferred consistency (smooth or slightly chunky).

Assembling in dish:

Spray a 9x13 inch dish well. Spread the mashed sweet potato mixture into an even, level layer. Scatter mini marshmallows uniformly across the top, covering everything edge to edge. **Gently press down** so they sink slightly into the filling.

Baking and toasting:

Bake at 400 degrees Fahrenheit. **Set a timer for 10 minutes** and begin watching closely. Continue baking for an additional 2 to 10 minutes until the marshmallows are gorgeously golden brown. Remove immediately to prevent burning.

Resting:

Let the casserole rest for about **5 minutes** before serving so it sets up slightly and isn't molten hot.

I learned about the marshmallow burning situation when I got distracted helping someone in another room during that final baking step. The marshmallows had gone from golden to charcoal in literally no time, and the smell of burnt sugar took hours to leave the house. Now I stand in front of the oven watching those marshmallows like a hawk.

Different Ways to Make It

• Add a **pecan streusel topping** instead of or in addition to marshmallows for crunch and nutty flavor.
• Use **brown sugar** instead of maple syrup for a more traditional molasses sweetness.
• Mix in some **vanilla extract** for extra warmth and depth.
• Add **orange zest** to the filling for bright citrus notes.
• Use **coconut milk** instead of butter for a dairy-free version.

Keeping and Reheating

• The casserole keeps in the refrigerator for up to 5 days. The marshmallows will deflate and get sticky.
• Reheat the whole dish covered with foil in a **350-degree oven** for about 20 minutes.
• The sweet potato filling can be **made ahead** and stored in the fridge for up to 2 days before assembling and baking.
• **Do not add the marshmallows until right before baking** or they will dissolve into the filling.

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The simplicity is what makes it work—no fancy ingredients or complicated techniques, just sweet potatoes mashed with butter and syrup then topped with marshmallows like people have been doing for generations. The nostalgic factor makes this special beyond just the taste, connecting everyone at the table to holiday memories and family traditions.

Frequently Asked Questions

→ Can I use canned sweet potatoes instead?

You can, but fresh tastes way better. If you do use canned, drain them really well and skip the roasting step. You'll need about 3-4 cans.

→ Why are my marshmallows burning?

Marshmallows toast super fast. Check them every couple minutes after the 10 minute mark. Some ovens run hot and will toast them in 8 minutes.

→ Can I make this ahead of time?

Yes! Make the sweet potato mixture up to 2 days ahead and keep it covered in the fridge. Add the marshmallows and bake right before serving.

→ What if I don't like marshmallows?

Try a pecan streusel topping instead. Mix chopped pecans with brown sugar, flour, and melted butter, then sprinkle it on top before baking.

→ Can I use regular sized marshmallows?

Sure, but mini marshmallows cover the top more evenly. If using regular ones, cut them in half or just space them out across the top.

→ How do I know when the sweet potatoes are done roasting?

They should be really soft when you poke them with a fork. The skin might look wrinkled and some syrup might leak out. That's perfect.