Let’s talk about the side dish that steals the show every single holiday season: Sweet Potato Casserole. And not just any version - oh no, this is the good stuff. I’m talking rich, creamy mashed sweet potatoes, buttery brown sugar crumble on top, and a glorious layer of toasted marshmallows that would make your grandma clutch her pearls in pride! If you grew up in the Midwest like I did, you know this dish wasn’t optional at Thanksgiving or Christmas. It was practically a guest of honor.

This sweet potato casserole is old-fashioned in the very best way. It takes a perfectly nutritious veggie, adds an unreasonable (but highly encouraged) amount of butter and sugar, and then crowns the whole thing with melty, golden marshmallows. Health food? Absolutely not. Delicious? Ohhh yes. Let’s get into it!

Ingredients You’ll Need:

For the casserole base:

• 4 cups peeled, cubed sweet potatoes
• 2 large eggs
• ½ cup granulated sugar
• ½ cup milk
• 4 tablespoon butter, softened
• ½ teaspoon vanilla

For the topping:

• ½ cup brown sugar
• ⅓ cup all-purpose flour
• 3 tablespoon butter, softened
• 2 ½ to 3 cups mini marshmallows (because more is more)

Let’s Make It:

Prep time, baby! Preheat that oven to 325°F. You’ll also want to grease up a 9x13 casserole dish and set it aside like a stage waiting for its star.

Boil & mash: Peel and cube your sweet potatoes, toss them into a big saucepan, cover with water, and boil for about 12–15 minutes. Once they’re fork-tender, drain the water and mash ‘em up! (No need to be fancy here - rustic is charming.)

Mix it up: In a large bowl, stir in the eggs one at a time—this helps keep everything nice and smooth. Then add sugar, milk, butter, and vanilla. Mix until it’s dreamy and creamy.

Bake round one: Pour the sweet potato mix into your prepared baking dish. In a separate bowl, combine the brown sugar and flour, then cut in the butter until it’s crumbly and irresistible. Sprinkle it right over the top of the casserole. Pop it into the oven and bake for 30 minutes.

Marshmallow magic time: Now here comes the drama. Take the casserole out, turn the oven to broil, and layer those mini marshmallows on top. Slide it back in for just 1–2 minutes. Stay close—those babies go from toasted to torched in a flash!

Set & serve: Let the casserole set for about 5 minutes before serving… if you can wait that long. The smell alone will have people hovering like vultures.

Storage & Make-Ahead Tips:

• Make it ahead: You can totally prep the sweet potato mixture and the crumble topping a day early—just hold off on the marshmallows until right before baking.
• Leftovers: Store any leftovers in the fridge for up to 4 days. Reheat in the oven to get that topping crispy again!
• Freezer-friendly: You can freeze the sweet potato base without the topping for up to 2 months. Thaw, top, and bake when ready!

Substitutions & Twists:

• Dairy-free? Swap the milk and butter for your favorite plant-based versions!
• Nutty twist: Add chopped pecans to the crumble topping for a little crunch (and extra Southern charm).
• No marshmallows? Blasphemy—but okay. Top with just the brown sugar crumble and call it a day.

Yield: 12

Old Fashioned Sweet Potato Casserole

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This Sweet Potato Casserole is a classic holiday favorite with creamy, mashed sweet potatoes topped with a buttery brown sugar crumble. It’s a warm, comforting side dish that pairs perfectly with turkey, ham, or any festive meal!

Prep Time 25 minutes

Cook Time 30 minutes

Additional Time 7 minutes

Total Time 7 minutes

Ingredients

• 4 cups peeled, cubed sweet potatoes
• 2 large eggs
• ½ cup granulated sugar
• ½ cup milk
• 4 tablespoon butter, softened to room temperature
• ½ teaspoon vanilla

Instructions

1. Preheat the oven to 325 degrees. 
2. Peel and cut sweet potatoes into 1 inch cubes. Add to a large saucepan, cover with water, and cook for 12-15 minutes over medium/high heat.
3. Once the potatoes are tender, drain the water, then mash them.
4. Add the mashed sweet potatoes to a large bowl, then mix in the eggs one at a time.
5. Next, mix in the sugar, milk, butter, and vanilla until you’ve reached a smooth consistency. 
6. Pour the mixture into a 9x13-inch casserole dish.
7. Combine the brown sugar and flour in a small bowl, then cut in the butter with a fork until you have small clumps.
8. Sprinkle the topping evenly over the sweet potato mixture, then transfer to the oven and bake for 30 minutes.
9. Remove from the oven and turn it onto broil.
10. Sprinkle marshmallows over the top of the sweet potato casserole in a single layer. Return to the oven to broil for 1-2 minutes until the marshmallows are slightly toasted. NOTE: You will need to watch closely so they do not burn.  
11. Remove from the oven and allot to set for 5 minutes, then serve.

Nutrition Information:

Yield:

12

Serving Size:

1
Amount Per Serving: Calories: 170Total Fat: 5gSaturated Fat: 3gUnsaturated Fat: 2gCholesterol: 42mgSodium: 56mgCarbohydrates: 29gFiber: 2gSugar: 11gProtein: 4g

Whether you're serving it next to turkey, ham, or honestly just eating a scoop out of the fridge with a spoon (no judgment), this old fashioned sweet potato casserole brings that cozy, nostalgic flavor that makes any meal feel like a celebration.

Here are some more great recipes you might love:

• Old Fashioned Cranberry Sauce (Just Like Mom Made!)
• Old-Fashioned Rocky Road Christmas Cups (Just Like Grandma Made!)
• Frugal Holiday Meals That Still Impress Your In-Laws