Sweet Potato Casserole with Marshmallows and Cinnamon Streusel — Holiday Recipe
I remember the first time I brought this Sweet Potato Casserole with Marshmallows and Cinnamon Streusel to a family gathering — the caramelized marshmallow edges and the crunchy cinnamon streusel disappeared faster than I could dish it out. Growing up, sweet potato dishes were a staple at holiday tables across the South and beyond, blending Native American, African, and European influences into the warm, sweet-savory casseroles we love today. This version balances creamy, lightly spiced sweet potatoes with a buttery oat streusel and toasty mini marshmallows on top — the kind of comfort food that feels like a hug. If you love cozy holiday sides, this recipe will likely become a new favorite. Check out a fun savory sweet-potato twist like these crispy oven-baked sweet potato fries for other ways to enjoy sweet potatoes.
Who is this recipe for?
- This recipe is perfect for holiday hosts, busy parents, potluck contributors, and anyone who loves a nostalgic, comforting side dish.
Core ingredients overview:
- This dish combines 4 cups cooked mashed sweet potatoes, brown sugar, milk, butter, vanilla, salt, mini marshmallows, and a cinnamon streusel made with flour, oats, brown sugar, cinnamon, and butter to create a creamy, lightly sweet casserole with a crunchy, spiced topping. For more cozy sides and comforting recipes, explore this creamy and comfort recipes collection.
Tools & Ingredients
Tools you’ll need:
- 9×13-inch baking dish
- Oven (preheated to 350°F / 175°C)
- Large mixing bowl
- Small mixing bowl
- Potato masher or ricer (if cooking your own potatoes)
- Measuring cups and spoons
- Pastry cutter or fork
- Rubber spatula or spoon
- Baking spray or butter to grease the dish
- Cooling rack
For more about the recipe author and kitchen tips, see about the author.
Ingredients (with a brief benefit for each):
- 4 cups sweet potatoes, cooked and mashed — nutritious, naturally sweet base rich in vitamin A.
- 1/2 cup brown sugar — adds caramel-like sweetness and moisture.
- 1/2 cup milk — creates a creamy, smooth texture.
- 1/4 cup butter, melted — adds richness and helps bind the mixture.
- 1 teaspoon vanilla extract — enhances sweetness and aroma.
- 1/2 teaspoon salt — balances flavors and brings out sweetness.
- 2 cups mini marshmallows — provide a nostalgic, toasty topping and creamy melt.
- 1/2 cup all-purpose flour — forms the base for a crisp streusel.
- 1/2 cup rolled oats — adds heartiness and a pleasant chew to the streusel.
- 1/2 cup packed brown sugar — sweetens and caramelizes the streusel.
- 1 teaspoon ground cinnamon — warms and spices the dish with aromatic depth.
- 1/4 cup butter, softened — binds the streusel and creates a tender, crumbly topping.
Instructions
- Preheat the oven to 350°F (175°C).
- In a large bowl, mix the mashed sweet potatoes, 1/2 cup brown sugar, milk, melted butter, vanilla extract, and salt until smooth.
- Pour the sweet potato mixture into a greased 9×13-inch baking dish and spread it into an even layer.
- In another bowl, combine the flour, oats, 1/2 cup brown sugar, and cinnamon. Cut in the softened butter with a pastry cutter or fork until the mixture is crumbly.
- Sprinkle this streusel mixture evenly over the sweet potato layer.
- Bake in the preheated oven for 25 minutes.
- Remove from the oven and top with mini marshmallows, spreading them evenly across the casserole.
- Return to the oven and bake for an additional 10 minutes or until the marshmallows are golden brown and the streusel is crisp.
- Let cool slightly before serving so the casserole sets and is easier to portion.
FAQ
Q: Can I freeze this recipe?
A: Yes — you can assemble the casserole without marshmallows and wrap it tightly in plastic wrap and foil. Freeze for up to 2 months. Thaw in the refrigerator overnight, then bake and add fresh marshmallows in the final 10 minutes.
Q: What can I use instead of mini marshmallows?
A: You can omit marshmallows and sprinkle chopped pecans or candied pecans on top for crunch, or use a light dusting of cinnamon sugar for a simpler finish.
Q: Can I make this ahead of time?
A: Absolutely. Prepare through step 5, cover, and refrigerate for up to 24 hours. Bake when ready, then add marshmallows and finish as directed.
Q: Can I reduce the sugar?
A: Yes — reduce brown sugar slightly in the base or streusel to suit your taste. Keep in mind that sweetness balances the savory notes of the potato and the marshmallows.
Tips & Tricks
- Use room-temperature ingredients: Let the softened butter and milk sit at room temp so they incorporate smoothly for a silky sweet potato layer.
- Don’t overwork the streusel: Cut the butter into the flour and oats until just crumbly — overmixing can make the topping dense.
- Toast edges if needed: If marshmallows brown unevenly, briefly broil on low while watching closely for a uniform golden top.
- Customize texture: For an ultra-smooth filling, press cooked sweet potatoes through a ricer; for more rustic texture, mash by hand and leave small lumps.
Conclusion
If you’d like variations or another take on this classic, see this delicious Sweet Potato Casserole with Marshmallows and Streusel for a pecan-streusel twist, explore extra tips at Sweet Potato Casserole – What’s In The Pan, or compare techniques with the Sweet Potato Casserole Recipe | My Baking Addiction for more inspiration.
Enjoy this cozy side with family and friends — and don’t forget to share the leftovers! Always add
tag after Directions.
Sweet Potato Casserole with Marshmallows and Cinnamon Streusel
Ingredients
- 4 cups sweet potatoes, cooked and mashed Nutritious, naturally sweet base rich in vitamin A.
- 1/2 cup brown sugar Adds caramel-like sweetness and moisture.
- 1/2 cup milk Creates a creamy, smooth texture.
- 1/4 cup butter, melted Adds richness and helps bind the mixture.
- 1 teaspoon vanilla extract Enhances sweetness and aroma.
- 1/2 teaspoon salt Balances flavors and brings out sweetness.
- 2 cups mini marshmallows Provide a nostalgic, toasty topping and creamy melt.
- 1/2 cup all-purpose flour Forms the base for a crisp streusel.
- 1/2 cup rolled oats Adds heartiness and a pleasant chew to the streusel.
- 1/2 cup packed brown sugar Sweetens and caramelizes the streusel.
- 1 teaspoon ground cinnamon Warms and spices the dish with aromatic depth.
- 1/4 cup butter, softened Binds the streusel and creates a tender, crumbly topping.
Method
- Preheat the oven to 350°F (175°C).
- In a large bowl, mix the mashed sweet potatoes, 1/2 cup brown sugar, milk, melted butter, vanilla extract, and salt until smooth.
- Pour the sweet potato mixture into a greased 9x13-inch baking dish and spread it into an even layer.
- In another bowl, combine the flour, oats, 1/2 cup brown sugar, and cinnamon. Cut in the softened butter with a pastry cutter or fork until the mixture is crumbly.
- Sprinkle this streusel mixture evenly over the sweet potato layer.
- Bake in the preheated oven for 25 minutes.
- Remove from the oven and top with mini marshmallows, spreading them evenly across the casserole.
- Return to the oven and bake for an additional 10 minutes or until the marshmallows are golden brown and the streusel is crisp.
- Let cool slightly before serving so the casserole sets and is easier to portion.
