Sweet Potato Casserole with Marshmallows

This impressive Sweet Potato Casserole with Marshmallows is a secret family recipe that is easy to make with just a few simple ingredients! Can you guess what we use to make it extra creamy with the perfect amount of sweetness?

Table of Contents

• My Mom’s Famous Sweet Potato Casserole!
• What’s The Secret To Making The Best Sweet Potato Casserole?
• Recipe Ingredients
• Can I Add An Egg?
• How To Make Sweet Potato Casserole
• The Most Frequently Asked Questions
• Can You Prep This Casserole Ahead?
• What To Serve With This Dish?
• How To Store Leftovers
• Get the Recipe

My Mom’s Famous Sweet Potato Casserole!

If you ask me, there is only one Sweet Potato Casserole recipe that matters and that is my Mama’s homemade sweet potato casserole with marshmallows! This old-fashioned casserole is easy to make, and can be made a day ahead, making it one of the best Thanksgiving side dishes.

I make it every year and our holiday table just wouldn’t be the same without it. Over the years, I have tried many different recipes and this one is by far the best version I have ever tasted. The perfectly spiced and sweetened sweet potatoes are topped with marshmallows that are toasted until perfectly browned. Keep scrolling to find out my Mom’s secret ingredient!

If you aren’t a fan of marshmallows and sweet potatoes, you should try this recipe for Sweet Potato Casserole with A Pecan Topping! And if you want to save space in the oven, you could also try my easy recipe for Crockpot Sweet Potatoes with Marshmallows!

What’s The Secret To Making The Best Sweet Potato Casserole?

I think it all comes down to that secret ingredient my Mom adds. It comes in a can and is extra creamy. Any guesses what it is?! Why, it’s sweetened condensed milk of course!

If you have been around here long enough, you know how much my Mom likes to sneak that sweet nectar into recipes. Just like in the now famous Mama’s Best Banana Pudding, the sweetened condensed milk adds the perfect sweetness and creaminess to this Sweet Potato Casserole. 

I have tried making this casserole recipe many other ways…like with milk, cream and even evaporated milk. I have also tried regular sugar, brown sugar and maple syrup to sweeten this casserole, but I always come back to using sweetened condensed milk! There is something magical about the perfect sweet and creamy flavor it adds to this casserole.

Recipe Ingredients

There is what you’ll need to make this old fashioned sweet potato casserole:

• Sweet Potatoes: I like to bake my sweet potatoes, instead of boiling them. I find it easier and I can do it a few days ahead. However, you can also boil them!
• Butter
• Sweetened Condensed Milk: This secret ingredient that makes this casserole extra creamy and perfectly sweet.
• Spices: Cinnamon, Nutmeg and Salt are all you need! However, if you prefer, you can also use a few dashes of pumpkin pie spice.
• Marshmallows: I like to use big marshmallows, but you can also use mini marshmallows instead. It really is a personal preference. I like a lot of toasted marshmallow on top!

Can I Add An Egg?

Sure! Some people add eggs to their sweet potato casserole which makes your casserole turn out more light in texture, which is more of a Sweet Potato Soufflé.

Personally, adding an egg changes the texture and it’s not the classic Thanksgiving casserole that I am personally searching for. However, if you like to add eggs, please by all means, whip in an egg to the sweet potatoes before adding them to the casserole dish.

How To Make Sweet Potato Casserole

Making this casserole is super easy and quick! Here’s how you do it:

• Prepare the sweet potatoes: The first step is to boil your peeled and cubed sweet potatoes in water on the stove until fork tender. (You can also bake the sweet potatoes and then peel off the peels.)
• Add butter, condensed milk and spices: Then we add the melted butter, sweetened condensed milk, cinnamon, nutmeg and salt.

• Mash everything together: Mash away until smooth and transfer the sweet potato mixture into a greased 9×13 casserole dish.
• Top with marshmallows: Load on all those marshmallows on top of the sweet potato casserole. I like to use large marshmallows — just look at that glorious marshmallow to sweet potato ratio — but you can use minis if you prefer. 
• Heat in the oven to toast the marshmallows: I bake the casserole at 350°F for a few minutes to make sure everything is hot and to let the marshmallows on top get perfectly toasted.

The Most Frequently Asked Questions

Can You Prep This Casserole Ahead?

Absolutely! I always make this sweet potato casserole the day before to save me stress the day of Thanksgiving. I also included the full make ahead steps and directions in the Sweet Potato Casserole recipe below as well! Here’s how I prep it ahead.

1. If you want to make this casserole ahead of time, follow all steps but stop right before you put the marshmallows on top. At this point, cover the casserole dish tightly with a lid, cling warp or foil. Then keep it refrigerated until you are getting close to being ready to serve it. 
2. When you are ready to serve it, take it out of the fridge and let it warm up a little on the counter.
3. Heat the casserole in oven for 15 minutes (still covered with foil), then remove from oven and carefully top with marshmallows. Then bake it a little longer, uncovered, just until the marshmallows have toasted on top!
4. This casserole can also sit on the counter for a few hours and wait for your other Thanksgiving side dishes to be ready. Then they can all go into the oven together when you are getting close to eating.

What To Serve With This Dish?

Sweet potatoes are so versatile, that there are a ton of dishes that will go great along side them. Here are a few of my favorites:

• Ham/Turkey: Of course, salty ham or tender turkey will go great with this sweet potato casserole. I love this easy Crockpot Ham Recipe, but if you want to impress your guests, try my Baked Ham with Orange Glazed Ham! I also have a great tutorial on how to make the best Thanksgiving Turkey!
• Vegetables: Everything for this homemade Green Bean Casserole to these Creamy Baked Brussel Sprouts will go wonderfully with sweet potatoes. If you are serving a holiday meal, I also love this Jiffy Corn Casserole!
• Potatoes: What goes with potatoes? More potatoes! Just instead of sweet, the savory kind. These Garlic Mashed Potatoes are always the talk of the table, but I also love this Cheesy Potato Casserole with crispy topping.
• Bread: Everything from this quick and easy Beer Bread, to these homemade Texas Roadhouse Rolls or Southern Buttermilk Biscuits!

How To Store Leftovers

This casserole is best served fresh, but leftovers can be stored to be enjoyed another day. The marshmallows tend to not hold their shape, especially upon reheating, but it is still delicious!

If we have a lot of leftovers, I will store them in the casserole dish wrapped with saran wrap. However, we usually only have a little left, so I place them in an air tight container and store them in the fridge for up to 5 days. Try not to store them in a zip lock bag as the marshmallows usually turn to mush when stored that way.

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Yield: 10 - 12 Servings

Sweet Potato Casserole Recipe

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This easy Sweet Potato Casserole recipe is a family favorite that's loaded with marshmallows, butter, cinnamon and a secret ingredient to create the best Thanksgiving side dish!

Prep Time 25 minutes

Cook Time 15 minutes

Total Time 40 minutes

Ingredients

• 2.5 lbs sweet potatoes, peeled and diced
• 8 tablespoons (1 stick) butter, melted
• 1 (14 oz) can sweetened condensed milk
• 1 tablespoon cinnamon
• 1/2 teaspoon nutmeg
• 1/2 teaspoon salt
• 1 (16 oz) bag large marshmallows

Instructions

1. Preheat oven to 350°F. Spray a 9x13 casserole dish with non stick spray and set aside. 
2. In a large stock pot, add sweet potatoes and cover with water. Cover pot with lid, bring to a boil and cook until fork tender, about 15 minutes. 
3. Drain potatoes and transfer back to pot. Add butter, sweetened condensed milk, cinnamon, nutmeg and salt. 
4. Mash away until nice and smooth. Pour potato mixture into prepared baking dish and smooth out the top.  
5. Line the top of the casserole with marshmallows and bake until marshmallows are lightly toasted, about 15 to 20 minutes.

Notes

Make Ahead Note: If you make this ahead, do not add marshmallows ahead of time. Instead, store the casserole (without marshmallows) in the fridge covered tightly with foil. Heat them in oven for 15 minutes (still covered with foil), then remove from oven and continue on with step #5. 

Store Leftovers: Store any leftovers in an airtight container for up to 5 days. When you reheat it, the marshmallows will likely evaporate a little. It will still taste delicious, but will look a little different.

Recommended Products

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• Freezer-to-Oven Safe 9x13 Glass Casserole
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  OXO Potato Masher

Nutrition Information:

Yield:

12 servings

Serving Size:

1
Amount Per Serving: Calories: 99Total Fat: 0gSaturated Fat: 0gTrans Fat: 0gUnsaturated Fat: 0gCholesterol: 1mgSodium: 127mgCarbohydrates: 22gFiber: 3gSugar: 8gProtein: 2g

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