If you’re always reaching for seconds of sweet potato casserole, my southern Sweet Potato Casserole is callin’ your name boo! I make sure it ain’t overly sweet by balancing the smooth sweet potato filling with a buttery streusel topping and toasted marshmallows. It’s never missing from my holiday table and after you taste it, I know it won’t be missing from yours either.
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How to make Southern Sweet Potato Casserole
Step 1: Fill a large pot with sweet potatoes and water about an inch higher than the potatoes. Bring the water to a boil cook until the potatoes are fork tender, and drain potatoes.
Step 2: Blend the potatoes until mostly smooth using a hand mixer or a masher.
Step 3: Add the butter, sugar, cream, vanilla, cinnamon, and nutmeg and mix until well combined and the potatoes are smooth.
Step 4: Spoon the mashed potatoes into the dish and smooth with a spatula.
Step 5: Combine the flour, sugar, oats, cinnamon, and nutmeg in a medium bowl and blend together with a whisk. Add melted butter to dry ingredients and mix with a fork creating a crumbly mixture.
Step 6: Add marshmallows to the top of mashed sweet potatoes. Sprinkle the crumble topping over the top.
Step 7: Bake until crumble is crisp and marshmallows are golden brown.
Sweet Potato Casserole Recipe
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Ingredients
For Sweet Potatoes
- 3 1/2 lbs sweet potatoes
- 1/3 cup salted butter
- 2/3 cup light brown sugar packed
- 3/4 cup heavy whipping cream
- 1 tbsp vanilla extract
- 1 tsp ground cinnamon
- 1/4 tsp ground nutmeg
For the Crumble Topping
- 1/2 cup all purpose flour
- 6 tbsp light brown sugar packed
- 1/4 cup old fashioned oats
- 1/2 tsp ground cinnamon
- 1/8 tsp ground nutmeg
- 4 tbsp salted butter melted
- Marshmallows for topping 6 rows of 4 cover the whole pan
Instructions
For the Potatoes
- Fill a large 8 qt pot with sweet potatoes and water about an inch higher than potatoes. Bring to a boil over high heat. While the potatoes are boiling, reheat the oven to 350 F. Grease a 9×13" casserole dish. Cook until fork tender, about 20-30 minutes, depending on the size of the potatoes. Completely drain potatoes and place back into the pot.
- Peel the skin off the potatoes and add to a large mixing bowl. Using a hand mixer (or a masher), blend potatoes until mostly smooth. Next add butter, sugar, cream, vanilla, cinnamon and nutmeg and mix until well combined and potatoes are smooth.
- Spoon mashed potatoes into dish and smooth with a spatula.
For the Crumble Topping
- Whisk together flour, sugar, oats, cinnamon and nutmeg in a medium bowl. Melt butter in a microwave safe bowl. Add melted butter to dry ingredients and mix with a fork until well combined to create crumbs. Sprinkle the potatoes with the topping.
- Add marshmallows to top of crumble topped potatoes. Create 6 rows of 4 regular sized marshmallows to cover the whole pan.
- Bake for 20-25 minutes or until crumble is crisp and marshmallows are golden brown. You can also broil marshmallows a bit if you want them to have a more torched look.
Notes
How to store & reheat Southern Sweet Potato Casserole
After your casserole cools down, cover it tightly with plastic wrap or foil (or transfer it to an airtight container), and pop it in the fridge. Easy storage y’all! To reheat, transfer the leftover casserole to a baking dish with the toppings on the top layers as much as possible. You can add more marshmallows and oat crumble mixture to the top if you want it to cook up crispier again the second time around. Heat in a 350°F oven until heated through, about 15-20 minutes. You can also reheat it in the microwave but the topping will lose a bit of its crispness.How long will Southern Sweet Potato Casserole last in the fridge?
In the fridge, this casserole will stay good for about 3 to 5 days. But honestly boo, I don’t think it will stay untouched for that long!Can I freeze this old fashioned sweet potato casserole?
Yep! It freezes great! You can freeze it right in the baking dish or carefully transfer it to a storage container with the toppings on top. Store it in the freezer for up to three months.Nutrition
Recipe Tips
- Mash ‘Em Real Good: Take your time mashing those sweet potatoes y’all. Get in there with a hand mixer or a sturdy masher and make them velvety.
- Watch That Toast: Keep a close eye on them marshmallows while they’re in the oven.
- Taste Before You Sweeten: Depending on how sweet your potatoes are, you might need to tweak the sugar.
- Layer It the Way You Like: The ratio of sweet potato, crumble and marshmallow is yours to play.
- Broil the Top: For a more torched look on the marshmallows, place the casserole under the broiler after cooking it in the oven.
Ingredient Notes
- Fresh Sweet Potatoes: I swear by using fresh sweet potatoes because the flavor is unmatched, but if you’re not in the mood to boil and peel, use canned sweet potatoes. Just drain ’em well, so your casserole isn’t too watery.
- Heavy Whipping Cream: Half and half is a good swap.
- Light Brown Sugar: or dark brown works. Also make homemade brown sugar with granulated and molasses if you ran out.
- Butter: If all you’ve got is unsalted butter, use and add some salt.
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Serving Suggestions
- Perfect Mains: When you’ve got a rich dish like this sweet potato casserole, you need a savory main to balance it out. Fry a juicy turkey, slow cook a honey glazed ham, or make a crispy roast chicken.
- Get Your Sides On: You can’t go wrong with more holiday classics boo! Serve this casserole alongside some creamy white cheddar mac n cheese, a green bean casserole, or tangy cranberry sauce.
- Bready Goodness: Try some soft dinner rolls or buttery cornbread. They’re the perfect way to round out your plate.
- Finish Sweet: This is a sweet side, I know, but there’s always space for dessert! A slice of pecan pie, some warm bread pudding, or a classic pumpkin pie.
Recipe Help
Of course, boo! Whip up your sweet potato mixture up to three days in advance and store it in your refrigerator. Be sure to leave the marshmallows off until you’re ready to bake. Let the casserole dish sit out at room temperature for at least 30 minutes before topping and baking.
It’s likely because there was too much liquid in the sweet potatoes. Make sure to fully drain your potatoes after boiling and, if using canned, let them sit in a colander for a bit to get rid of any excess moisture. Also, if you want a thicker consistency, just use 1/2 cup of heavy whipped cream.
You can, but yams and sweet potatoes have slightly different textures and flavors. Yams are usually starchier and less sweet, so if you go this route, you might want to bump up the sugar and spices.
Holy monkey, this is amazing! Will make it again for sure!
Wonderful!!
This is THE sweet potato casserole you want for thanksgiving! The potatoes are creamy, and the crumble topping adds the perfect amount of texture. Now I want a plate!
Wow thank you so much Kelly!
How many sweet potatoes does this recipe call for? I would really love to make this for Christmas
Hi Nita, you are going to need 3.5 pounds of sweet potatoes. You can find all the recipe ingredients, including the amounts for each in the recipe card above the comment section. Hope everyone enjoys!
Very Good!! It tasted good before I Baked it.
Thank you so much!!
Do you boil the potato’s whole or cut into pieces?
Cut into pieces.
I made this today for Thanksgiving and it was delicious. I had some friends here from Louisiana and they said they were perfect southern sweet potatoes. That made me so happy to have them really love them. Thank you for this recipe.
Wow I’m so glad you and everyone enjoyed it!
Hi. I want to try this, but all i have is a large can of sweet potatoes. Would you keep the rest of the recipe the same? Drain them? Would it work? Thanks.
I would definitely drain them.
Made this today and it is absolutely delicious!!! Love the flavor and the crumble added an extra layer of texture and flavor. Excellent recipe, has become my favorite Sweet Potato Casserole recipe!!