Smooth and creamy with a gooey and crunchy topping, this Gluten Free Sweet Potato Casserole will be the only one you'll ever make again.
Gluten Free Sweet Potato Casserole was originally posted on November 16, 2022 and has been updated with new pictures, some new copy, and a video.
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When I was young, I never tried sweet potatoes because I couldn't think of a sweet potato as something other than a type of potato. How in the world could you put cinnamon and sugar anywhere NEAR a potato, or worse--marshmallows!! Yuck! Growing up, we used to celebrate Thanksgiving with our neighbors and someone would always make a sweet potato casserole. I'd skip over it ever year. Thought it looked so gross.
My first husband's stepmom was as southern as southern could get and we often had Thanksgiving at their house. She made a sweet potato casserole that she called "sweet potato souffle" and I decided to give it a try. I was BLOWN AWAY! It was so insanely good--smooth and creamy with a brown sugar topping and mini marshmallows that were crunchy and gooey all at the same time. Why, oh why had I skipped over sweet potatoes all my life?!?!
When Thanksgiving comes around every year, it's pretty much unspoken gospel that I will be making this casserole. I've tried making other sweet potatoes for our dinner, to be adventurous and try new things. But I always come back to this one because it's so darn good and the family doth protests too much 😁
what you'll need to make this legendary casserole
- Mashed sweet potatoes - I think you can purchase cans of sweet potatoes for ease, but don't quote me on that. What I like to do is prep sweet potatoes a few weeks before Thanksgiving, mash them, and freeze them. Most of the time I bake them as that's the easiest method. Check out my method below.
- Eggs - eggs add body to the sweet potato filling. As a vegan alternative, you can use applesauce.
- Sugar - more on that below.
- Milk - you can substitute dairy-free milk and make this dairy free. Last year I made this with canned coconut milk for my daughter, who is vegan. She loved it!
- Kim's gluten free all purpose flour blend - you'll need a little bit of flour for the streusel. The streusel topping is sweet, but it's not crunchy like a normal streusel. It's more like a layer of brown sugary goodness that gets melty and almost syrupy.
- Marshmallows - is it even a sweet potato casserole without marshmallows? I once made this with homemade marshmallows, which was OUTSTANDING! But we have to make so many things from scratch that I just use store bought ones now. I love the large marshmallows, but you can use the minis. You can also use vegan marshmallows. I get mine from Trader Joe's.
Working with Sweet Potatoes
I used to peel, chop, and boil my sweet potatoes before mashing them. It was a pain in the you-know-what. All that peeling. And the chopping? Forgedaboutit! Too much work. I finally got smart and began baking my sweet potatoes whole. Game changer!!!!! I will never do it any other way. Put them on a parchment or foil-lined baking sheet, prick them with a fork a few times, and bake them at 400 F. When they're done about an hour later (give or take a few minutes, depending on their size), scoop out the flesh and mash. Easy peasy!!
If you happen to have leftover mashed sweet potatoes (I like to bake several potatoes at once), just cool them and put them in a ziptop bag and into the freezer. Then when you want to make something like sweet potato pancakes, sweet potato pie (the BEST), or sweet potato biscuits, you'll already be one step ahead.
How to Make Sweet potato Casserole
Combine sweet potatoes, sugar, eggs, milk, vanilla extract, salt, and melted butter in a large mixing bowl. Whisk until smooth.
Spread sweet potato mixture into the bottom of a baking dish.
Use a fork to cut flour into gluten-free flour blend and brown sugar in a medium bowl.
Sprinkle streusel mixture evenly over sweet potatoes in dish.
Place mini or large marshmallows over top of streusel in baking dish.
Bake at 350 F for 30-35 minutes, until marshmallows are fully toasted.
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A Word on Sugar
For all you sugar phobics out there, there is an unapologetically large amount of sugar in this casserole. This is a very southern recipe from a very southern older woman who could have cared less about how much sugar was in it. You won't be eating the whole casserole by yourself (at least I hope not!), and you're not going to eat it every single day of your life. On Thanksgiving Day, let your hair down. Live a little. Go back to your daily diet after turkey day.
But if you're still not convinced that it'll be okay (or if you're diabetic or can't have sugar for another reason), you can dial down the sugar. My suggestion would be to reduce the sugar in the sweet potato filling and NOT the streusel as the texture of the streusel would be "off" a little bit. Also, substituting some of the sugar with no-sugar-added applesauce would also work great.
sweet potato casserole faqs
YES!! Layer the sweet potatoes and streusel in a casserole dish and cover tightly with plastic wrap or foil. Refrigerate it for up to two days. On baking day, remove from the fridge, add marshmallows, and bake as directed. You can also freeze the casserole, before adding the marshmallows, for up to six weeks. Remove from the freezer the day before you want to serve it and place it in the refrigerator, still well wrapped. On baking day, remove the plastic wrap and add the marshmallows, baking as directed.
You can always put it in the microwave, but to re-crisp the toasted marshmallows, put it in a 350-degree oven for approximately 15 minutes.
Yes, you certainly can! To make dairy free, substitute the butter with vegan butter (or coconut oil) and the milk with any non-dairy milk of choice (I like canned coconut milk, but almond milk or any others will work). To make completely vegan, sub the eggs with applesauce (in equal amounts) and the marshmallows with vegan marshmallows (I get them at Trader Joe's).
More Recipes Using Sweet Potatoes
- Gluten Free Sweet Potato Biscuits
- The Best Gluten Free Sweet Potato Pie
- Gluten Free Sweet Potato Pancakes
I guarantee you'll be in heaven once you try this Gluten Free Sweet Potato Casserole. It's so easy and so delicious and your family will go crazy for it!

Gluten Free Sweet Potato Casserole
Ingredients
- 1 cup (200g) granulated sugar
- 3 cups (750g) *mashed sweet potatoes
- 1 teaspoon vanilla
- ¼ cup (60g) milk (a non-dairy milk may be substituted)
- ½ teaspoon salt
- 2 large eggs, at room temperature (for vegan, use ½ cup (120g) of applesauce)
- ¼ cup (57g) butter, melted (non-dairy butter may be substituted)
Streusel
- ½ cup (70g) Kim's all purpose gluten free flour blend (a store bought blend may work, but hasn't been tested)
- 1 cup (200g) brown sugar
- 3 tbsp (42g) butter, softened (non-dairy butter may be substituted)
Topping
- 1 10-ounce bag (283g) large or mini marshmallows (for vegan, substitute with vegan marshmallows)
Instructions
- Preheat oven to 350° F. Grease a 9 by 13-inch (or any similar size) baking dish and set aside.
- Combine mashed sweet potatoes with sugar in a large mixing bowl. Whisk until smooth. Add eggs, vanilla extract, milk, salt, and melted butter.
- Scoop into prepared baking dish and smooth the top.
- In a medium bowl, combine all streusel ingredients until crumbly (I like to use a fork). Sprinkle crumbs on top of sweet potatoes evenly. Top with marshmallows in a single layer.
- Bake for 30-35 minutes, or until marshmallows are well toasted.
Rosemarie Wood says
I make a version of this. I use canned sweet potatoes but fresh will work. I cut them up and put in a fry pan. I use some canned liquid or chicken broth. Add brown sugar and cook down a bit. I add some butter. I never use eggs or any type of milk and cook until the liquid thickens. Put in a oven proof dish and add lots of marshmallows on top and bake till the marshmallows are cooked till nice a golden.
Leilani says
Loved by all. Must do again.
Maggie Lawrence says
Amen sister! Never (at Thanksgiving) be like the ladies on the Titanic who regretted not having dessert. This recipe looks amazing. Thank you for sharing.
Shari says
Hi Kim, this was a big hit at our house this Thanksgiving. My husband said he didn’t like sweet potatoes, NOW this is his favourite dish, he was in shock at how much he loves these. Thanks once again for a great recipe. I’ll be making these again next year. Blessings
Kim says
Haha! That's terrific!! This dish is what made me a sweet potato lover, too 🙂
Wendy Jensen says
This is my favorite Thanksgiving dish ever!! Once you have it you'll want to make it every year. It's that good!
Kim says
Thanks, Wendy 😍