This Perfect Sweet Potato Casserole is a classic holiday treat that everyone looks forward to at Thanksgiving. It’s made with creamy mashed sweet potatoes, a touch of warming spices, and topped with those golden, toasty marshmallows that add just the right amount of sweetness and fluffy texture. The contrast between the smooth sweet potatoes and the gooey marshmallows on top makes this dish a real crowd-pleaser.
I love making this casserole because it always brings back those warm, cozy feelings of being with family and friends. One little tip I have is to watch the marshmallows closely when baking—they go from perfectly golden to burned before you know it! I usually switch the oven to broil for just a minute or two at the very end to get that perfect marshmallow topping.
Serving this dish fresh and warm straight out of the oven is the best way to enjoy it. It pairs wonderfully with turkey and all the trimmings, balancing out the savory flavors with its sweet, comforting goodness. Whenever I bring this casserole to a gathering, it disappears fast, and I love seeing everyone’s happy, satisfied smiles after a second (or third) helping.
Key Ingredients & Substitutions
Sweet Potatoes: Fresh sweet potatoes give the best flavor and texture. If you’re short on time, canned sweet potatoes can work but fresh makes it creamier and more natural.
Butter & Milk: Butter adds richness to the mash, and milk makes it smooth. For dairy-free versions, try coconut milk and a plant-based butter.
Spices: Cinnamon and nutmeg add warmth and depth. Feel free to adjust amounts to your taste or skip nutmeg if you’re not a fan.
Marshmallows: Mini marshmallows melt and toast perfectly. You can swap them for regular-sized marshmallows, but cut them up so they toast evenly.
Crumble Topping: The topping adds crunch and a little extra sweetness. Nuts are optional but bring a nice texture; substitute with pecans, walnuts, or skip if you prefer gluten-free.
How Do You Get the Marshmallows Golden Without Burning?
Toasting marshmallows just right can be tricky. Here’s how I do it:
- Bake the casserole covered at 350°F to warm through and melt the marshmallows slightly.
- Switch the oven to broil at the end—place the casserole on the top rack.
- Watch the marshmallows closely (about 1 to 3 minutes). They brown quickly, so don’t walk away!
- Once golden and puffy, remove from the oven immediately to prevent burning.
Using broil gives a perfect toasted top with a gooey center. If you don’t have a broiler, bake longer at 350°F until marshmallows brown gently.
Equipment You’ll Need
- Large pot – I use it to boil the sweet potatoes until tender, making them easy to mash.
- Mixing bowls – for combining ingredients and making the crumble topping.
- Masher or hand mixer – to get smooth, lump-free sweet potatoes.
- 9×13-inch baking dish – this size fits everything and makes serving easy.
- Measuring cups and spoons – for accurate ingredients, especially spices and liquids.
- Spatula or spoon – for spreading the mash evenly and sprinkling toppings.
- Broiler or oven with a broil setting – to toast the marshmallows perfectly (just keep a close eye!).
Flavor Variations & Add-Ins
Try swapping the marshmallows for toasted marshmallow bits or caramelized pecans for extra crunch. Or add a dash of ginger or clove for a spiced twist. For a savory touch, mix in some crumbled bacon or shredded cheese before baking.
Perfect Sweet Potato Casserole for Thanksgiving with Marshmallows
Ingredients You’ll Need:
Main Ingredients:
- 4 large sweet potatoes (about 3 pounds)
- 1/2 cup granulated sugar
- 1/4 cup unsalted butter, softened
- 1/2 cup milk (whole or 2%)
- 1 teaspoon vanilla extract
- 1/2 teaspoon ground cinnamon
- 1/4 teaspoon ground nutmeg
- 1/2 teaspoon salt
- 2 cups mini marshmallows
For the Crumble Topping:
- 1/2 cup all-purpose flour
- 1/2 cup light brown sugar, packed
- 1/4 cup unsalted butter, melted
- 1/2 cup chopped pecans or walnuts (optional)
- 1/2 teaspoon ground cinnamon
Time Needed
This recipe takes about 15-20 minutes to prepare and boil the sweet potatoes, 25-30 minutes to bake, plus an additional few minutes for broiling to toast the marshmallows. Altogether, plan for about 45-60 minutes from start to finish.
Step-by-Step Instructions:
1. Prepare the Sweet Potatoes:
Preheat your oven to 350°F (175°C) and lightly grease a 9×13-inch baking dish. Peel the sweet potatoes and cut them into chunks. Place them in a large pot of water and bring to a boil. Cook until very tender, about 15-20 minutes. Drain well.
2. Mash and Mix:
In a large bowl, mash the sweet potatoes until smooth using a potato masher or hand mixer. Add granulated sugar, softened butter, milk, vanilla extract, cinnamon, nutmeg, and salt. Mix well until combined and creamy.
3. Assemble the Casserole:
Spread the mashed sweet potato mixture evenly into the prepared baking dish.
4. Make and Add the Crumble Topping:
In a bowl, mix the flour, brown sugar, melted butter, chopped nuts (if using), and cinnamon until crumbly. Sprinkle this evenly over half of the sweet potato layer.
5. Add Marshmallows and Bake:
Spread mini marshmallows evenly over the other half of the sweet potato mixture. Bake uncovered for 25-30 minutes, until the casserole is hot and bubbly.
6. Toast the Marshmallows:
Switch your oven to broil. Place the casserole under the broiler for 1-3 minutes until the marshmallows are golden brown and toasted on top. Watch closely to prevent burning.
7. Serve and Enjoy:
Remove from oven and let rest for a few minutes. Serve your warm, creamy sweet potato casserole topped with gooey toasted marshmallows and crunchy crumble. It’s a perfect holiday side everyone will love!
Can I Make This Sweet Potato Casserole Ahead of Time?
Yes, you can prepare the mashed sweet potatoes and crumble topping a day in advance. Keep them refrigerated separately, then assemble and bake just before serving for the freshest taste.
Can I Use Frozen Sweet Potatoes?
Absolutely! Make sure to thaw them completely and drain any excess moisture before mashing to avoid a watery casserole.
How Should I Store Leftovers?
Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat gently in the oven to keep the marshmallows soft and the casserole warm.
What Can I Substitute for Marshmallows?
If you prefer, you can omit marshmallows and use a crunchy pecan or oat topping instead. Alternatively, try using toasted coconut flakes for a unique twist.
