Sweet Potato Casserole Recipe with Marshmallows (Gluten Free)

With a hint of warm spices, just the right amount of brown sugar, creamy sweet potatoes, and crunchy oat and pecan streusel topping, this classic Southern Sweet Potato Casserole recipe is a crowd-pleasing gluten free side dish! Don’t wait for the holidays to make it, whip it up to serve with a Sunday roast chicken or steak.

The wonderful thing about this classic Sweet Potato Casserole recipe is that it can double as a side dish or dessert. It’s traditionally served as a side dish for holiday meals, but I think it’s sweet enough to enjoy instead of pie!

And if you’re serving this up as a side dish there’s no reason to save it for the holidays only. This side dish pairs well with roast chicken, steak, or roast beef. It’s gluten free, so if you’re looking for gluten free side dish options, look no further.

Plus, this sweet potato side dish is easy to make and you can make it ahead of time. And let’s be honest, it’s a pretty delicious way to get in a serving of vegetables, right?!

What You’ll Love About This Sweet Potato Casserole Recipe

Aromatic spices like cinnamon, nutmeg, and a hint of cloves add depth of flavor.

Just a touch of brown sugar is the perfect pairing with the natural sweetness of sweet potato.

A crunchy oatmeal and pecan topping is the perfect way to offset the creamy texture of the potatoes.

The marshmallows get all toasty on top and make this casserole even more delicious!

Are Sweet Potatoes and Yams the Same?

No! Yams and sweet potatoes are not the same thing. However, it can get confusing because grocery stores sometimes cross-label these items. And what makes it more confusing is that there are multiple varieties of sweet potatoes!

To make this Sweet Potato Casserole recipe, look for tubers that have reddish or coppery-colored skin and deep orange-hued flesh.

You can read more about the difference between sweet potatoes and yams on The Kitchn, Bon Appetit, and The Spruce Eats.

Sweet Potato Casserole Ingredients and Substitutions

Sweet Potato Filling:

• Sweet potato – You can technically use either sweet potatoes or yams for this recipe. For best flavor, use fresh sweet potatoes or yams, not canned or frozen.
• Unsalted butter – We mash the sweet potato with butter for rich flavor.
• Light brown sugar – This adds notes of caramel and molasses in addition to sweetness.
• Milk – Whole milk, or any type of milk you like.
• Egg – You can omit the egg if you prefer; it acts as a binder in this recipe and gives the casserole a little bit of structure as well as rich flavor (from the yolk).
• Vanilla extract – This adds flavor and aroma.
• Salt – Salt is a natural flavor enhancer that pulls out the flavor of everything else.
• Cinnamon, nutmeg, and cloves – These warm spices pair well with sweet potato, and blur the lines between side dish and dessert!

Oatmeal Pecan Streusel Topping:

• Old-fashioned rolled oats – Quick oats will also work here, but your streusel topping won’t be as crumbly.
• Pecans – If pecans aren’t your thing, feel free to omit them or swap them out for any type of nuts you like.
• Light brown sugar – To sweeten our crumbly oat topping.
• Unsalted butter – For rich flavor.
• Cinnamon – Just a hint of cinnamon in the topping adds the perfect amount of warm flavor and aroma.
• Salt – This creates a balanced flavor profile, and ensures that the streusel isn’t bland.

Other:

• Coconut oil spray – This is to grease the pan; or you can use coconut oil, butter, or clarified butter (ghee).
• Mini marshmallows – I like to use mini marshmallows here because they’re easier to spread evenly on top of the casserole; however, regular marshmallows will work fine.

Instructions

Make the Sweet Potato Layer:

1. Preheat the oven to 400F. Line a small baking tray with foil.
2. Rinse and dry the sweet potatoes. Poke a few holes in each.
3. Place the potatoes on the prepared tray and roast until a paring knife inserted in the center of the largest potato slides right out, about 1 hour.
4. Cool the potatoes until they’re not too hot to touch.
5. Slice open each potato; scoop out the flesh into a large bowl and discard the potato skins.
6. Mash the sweet potato with the butter, and then mash in the brown sugar, milk, egg, vanilla, salt, cinnamon, nutmeg, and cloves.

Make the Oatmeal Pecan Topping:

1. Use a fork to combine all ingredients in a medium bowl.

To Assemble and Bake the Casserole:

1. Preheat the oven to 400F. Spray the inside of a 1.5-quart casserole dish with coconut oil spray.
2. Spread the sweet potato mixture evenly into the prepared casserole dish.
3. Sprinkle the oatmeal pecan topping evenly on top.
4. Bake (uncovered) until the topping is golden, about 15 to 20 minutes.
5. Remove from the oven and carefully sprinkle the marshmallows on top.
6. Return to the oven and bake (uncovered) until the marshmallows are golden, about 5 minutes.
7. Serve warm.

Sweet Potato Casserole Recipe Tips and FAQs

Should I Boil or Bake the Sweet Potatoes?

You can either boil or bake the sweet potatoes to make this dish. I’ve made this casserole both ways, and I slightly prefer it with roasted sweet potatoes. I find that it has a slightly richer and deeper sweet potato flavor.

However, if you prefer to boil the sweet potatoes to make this recipe, I give instructions on how to do that in the Notes section of the recipe below.

Pro Tip: If you boil the sweet potatoes to make this, there’s no need to peel or chop them first. Instead, you can boil them whole and then scoop the flesh out of the skin after they’re cooked.

Should Sweet Potato Casserole be Runny?

No, this casserole shouldn’t be watery. If you follow this recipe as directed, you should end up with rich and creamy sweet potatoes.

Pro Tip: If you decide to boil your sweet potatoes instead of roasting them for this recipe, make sure only to boil them until they’re tender and then drain them well so they don’t get waterlogged.

Why Are There Eggs in Sweet Potato Casserole?

The egg in this casserole acts as a binder and gives it just the right amount of structure.

Does Sweet Potato Casserole Freeze Well?

Yes! Sweet Potato Casserole freezes very well, which makes it a great side dish option for holiday meals, such as Thanksgiving or Christmas. You can make it ahead of time and stash it in the freezer until you want to serve it!

To Freeze Sweet Potato Casserole:

1. Make the casserole as directed in the recipe, except don’t do the final 15 to 20 minute bake.
2. Once the casserole has cooled to room temperature, lay a piece of plastic wrap directly on top of the oatmeal pecan topping and then wrap it with foil.
3. Label the casserole with the date and contents.
4. Freeze it for up to 3 months.

To Reheat Frozen Sweet Potato Casserole:

1. Let the Sweet Potato Casserole thaw. I usually put it on a baking tray (to catch any water) and thaw it at room temperature overnight.
2. Remove the foil and the plastic wrap on top of the casserole.
3. Bake at 400F (uncovered) until the topping is golden, about 15 to 20 minutes.
4. Remove from the oven and carefully sprinkle the marshmallows on top.
5. Return to the oven and bake (uncovered) until the marshmallows are golden, about 5 minutes.

What Goes Well with Sweet Potato Casserole?

• A classic roast chicken or roast turkey is a perfect pairing
• Grilled Ribeye
• Dutch Oven Pot Roast
• Beef Brisket

More Sweet Potato Recipes to Try

• Brown Sugar Sweet Potato Pumpkin Soup
• Easy Sweet Potato Hash
• Fudgy Sweet Potato Brownies
• Instant Pot Mashed Sweet Potatoes
• Jerk Roasted Chicken Thighs and Sweet Potato Dinner