Perfect Sweet Potato Casserole for Thanksgiving with Marshmallows is a classic dish that’s both sweet and comforting. Creamy mashed sweet potatoes meet a golden, toasty marshmallow topping that’s soft and slightly crisp in just the right spots. It’s the kind of side that feels like a warm, cozy hug on your holiday plate.
I love making this casserole because it always brings a little bit of extra joy to the table. The sweet potatoes are silky and smooth, and when those marshmallows start melting and turning golden brown, I know we’ve got something special. I usually add a pinch of cinnamon or nutmeg to give it a subtle warm flavor, which makes the whole dish even more inviting.
My favorite way to serve this is right out of the oven while the marshmallows are still gooey and soft. It pairs beautifully with turkey, mashed potatoes, and all those wonderful Thanksgiving fixings. Honestly, this casserole is one of the dishes that everyone looks forward to, and it’s always the first to go – so I make sure to double the recipe every year!
Key Ingredients & Substitutions
Sweet Potatoes: Fresh sweet potatoes are ideal for that natural sweetness and creamy texture. If you can’t find fresh ones, canned sweet potato puree works in a pinch but adds more moisture, so reduce milk slightly.
Sugars: Both granulated and brown sugar give depth—brown sugar adds a caramel note. You can swap brown sugar with coconut sugar for a subtle twist or reduce sugar if you prefer less sweetness.
Butter & Milk: Butter adds richness and milk helps with smoothness. Use salted butter and skip added salt if preferred. For dairy-free options, try vegan butter and almond or oat milk.
Spices: Cinnamon and nutmeg bring warm fall flavors. Feel free to add a pinch of ginger or allspice to customize the spice level.
Marshmallows: Mini marshmallows give that signature golden topping. If avoiding marshmallows, try a crunchy pecan and brown sugar topping for a different texture and flavor.
How Do You Get the Perfect Gooey Yet Toasty Marshmallow Topping?
Balancing marshmallow softness with a toasted top is key. Here’s how to get it right:
- After baking the sweet potato base, sprinkle marshmallows evenly on top.
- Bake at 350°F for 10–15 minutes, just until marshmallows puff up and start browning.
- Watch carefully near the end to avoid burning—they toast fast!
- For an even toastier finish, a quick 1-2 minute broil works but stay close to prevent burning.
This method keeps marshmallows soft inside with a lightly crisp top—super satisfying every bite!
Equipment You’ll Need
- Baking sheet – for roasting the sweet potatoes evenly.
- 9×13 inch baking dish – to bake and serve the casserole.
- Fork or knife – to pierce the sweet potatoes before baking.
- Large mixing bowl – to mash and mix the sweet potatoes with other ingredients.
- Potato masher or mixer – for smooth, creamy mash.
- Wooden spoon or spatula – to combine ingredients thoroughly.
- Measuring cups and spoons – for accurate ingredient amounts.
- Oven – essential for baking the casserole and toasting the marshmallows.
Flavor Variations & Add-Ins
- Stir in chopped pecans or walnuts before baking for crunch and nutty flavor.
- Add a splash of orange juice or zest to give a fresh, citrus twist.
- Mix in a teaspoon of vanilla extract or maple syrup for extra sweetness.
- Top with crumbled graham crackers or a streusel mixture for a different topping texture and added flavor.
Perfect Sweet Potato Casserole for Thanksgiving with Marshmallows
Ingredients You’ll Need:
- 4 large sweet potatoes (about 3 pounds)
- 1/2 cup granulated sugar
- 1/2 cup packed brown sugar
- 1/2 cup unsalted butter, melted
- 1/4 cup milk
- 2 large eggs
- 1 teaspoon vanilla extract
- 1/2 teaspoon ground cinnamon
- 1/4 teaspoon ground nutmeg
- 1/2 teaspoon salt
- 1 1/2 cups mini marshmallows
How Much Time Will You Need?
This recipe takes about 15 minutes to prep, 1 hour to bake the sweet potatoes, plus 25-30 minutes to bake the casserole base. Then, an additional 10-15 minutes to toast the marshmallows on top. Plan for roughly 2 hours total 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. Pierce each sweet potato several times with a fork and place them on a baking sheet. Bake for about 1 hour, or until they are very soft when pierced with a fork. You can also microwave the sweet potatoes on high for 8-10 minutes, turning them halfway through. Allow the sweet potatoes to cool slightly before handling.
2. Mash and Mix:
Peel the sweet potatoes and place the flesh into a large mixing bowl. Mash them until smooth using a potato masher or an electric mixer. Add the granulated sugar, brown sugar, melted butter, milk, eggs, vanilla extract, cinnamon, nutmeg, and salt. Stir until the mixture is creamy and well combined.
3. Bake the Casserole and Add Marshmallows:
Pour the sweet potato mixture into your prepared baking dish, smoothing it out evenly. Bake uncovered for around 25-30 minutes until the mixture is set and slightly firm. Remove the casserole from the oven, then evenly sprinkle the mini marshmallows over the top. Return it to the oven and bake for another 10-15 minutes, or until the marshmallows have melted and turned a beautiful golden brown. Let the casserole cool just a bit before serving and enjoy!
Can I Use Frozen Sweet Potato Puree Instead of Fresh Sweet Potatoes?
Yes, you can! Just thaw the frozen puree completely and drain any excess liquid before mixing it with the other ingredients to avoid a watery casserole.
How Do I Store Leftovers?
Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat gently in the oven or microwave, but note that the marshmallow topping may lose its toastiness.
Can I Make This Casserole Ahead of Time?
Absolutely! Prepare the casserole base up to a day ahead, refrigerate it, and add the marshmallows just before baking and toasting for best results.
What Can I Use Instead of Marshmallows?
If you prefer to skip marshmallows, try topping the casserole with a crunchy pecan streusel for a delicious alternative texture and flavor.
