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This light and fluffy gluten free sweet potato casserole filling is topped with a sweet, nubby crumble topping that everyone loves. If you were like me in assuming there was no way to make a sweet potato casserole that would be better than just puréed and roasted sweet potatoes, with maybe a touch of milk, this recipe is for you (us).
Why this recipe works
The filling contains only 1/4 cup of added sugar in the filling, which is just enough to lightly sweeten, but not so much that the filling tastes sweetened. And with all the other savory ingredients like gluten free stuffing covered in gluten free turkey gravy, you'll enjoy that touch of sweetness.
Of course, if you'd like to add gluten free marshmallows to the top, add them in the last 10 minutes of baking the casserole, just enough time to melt them a bit. You can also toast them under your oven's broiler for a few minutes before serving.
For the crumble topping
The topping is made with two different types of sugar, and plenty of butter. It isn't healthy and doesn't even pretend to be good for you.
But the nubbiness of the mixture holds its shape during baking just like it does on a gluten free coffee cake. But it's a thinner layer, with lots more cinnamon.
It is sweet, but it's also toasted and crunchy. So it adds the most amazing texture variation to that pillow-soft sweet potato filling.
How to prepare the sweet potatoes
Rather than peeling, chopping, and boiling or steaming the sweet potatoes for the filling in this sweet potato casserole, I always roast them in their skins. Roasting sweet potatoes intensifies their natural sweetness and even caramelizes some of it.
The result is a much more complex flavor that retains all of its flavors (and nutrients), unlike boiling which draws many of the nutrients out into the boiling water.
The skin of a sweet potato is very thin, and becomes paper-like when it's roasted. I bet you could even purée the sweet potatoes with their skins, rather than removing them for the filling.
Prepare the sweet potatoes ahead of time
Preparing the sweet potatoes can be done days ahead of time. That should make your whole gluten free Thanksgiving a little less stressful!
To roast them, wash them well with running water, then dry them thoroughly. Pierce through the skin of each all over the with the tines of a fork, and wrap it separately in aluminum foil.
Place the wrapped sweet potatoes on a rimmed baking sheet and roast in a preheated 375°F oven until a paring knife inserted in the center of the thickest part of each sweet potato doesn't encounter any resistance (45 minutes to 1 hour+, depending upon size).
Remove the sweet potatoes from the oven, unwrap them, and allow them to sit until they are cool enough to handle. Remove the skins (they should slip or peel right off), and set them aside to use in the filling recipe.
Ingredient substitutions
Dairy free
There is dairy in both the crumble topping and the filling, but they should both be replaceable. I'd use block-style vegan butter in each like Melt or Miyoko's Creamery brand. You could also use Earth Balance buttery sticks in the filling, but not in the crumble topping as it won't hold its shape properly during baking.
In place of the dairy milk in the filling, you can use any nondairy milk you like. I recommend using something unsweetened and unflavored, like unsweetened almond milk.
Egg free
For all 4 eggs, combine 3/8 cup (6 tablespoons) milk, 3/8 cup (6 tablespoons) Greek yogurt, and 2 1/4 tablespoons (20 grams) cornstarch, and add when you would add the eggs.
Oat-free
The oats in the crumble topping recipe with 1/4 cup (35 g) additional all purpose gluten free flour (for a total of 1 cup (140 g)). You could also replace the oats with an equal amount, by weight, flattened buckwheat or rice flakes. For a complete discussion of substitutions for oats in gluten free baking, please see our substituting oats guide.
Gluten Free Sweet Potato Casserole Recipe
Ingredients
For the crumble topping
- ¾ cup (105 g) all purpose gluten free flour blend, (See Recipe Notes)
- ½ teaspoon xanthan gum, (omit if your blend already contains it)
- ¼ cup (25 g) gluten free old-fashioned rolled oats, (See Recipe Notes)
- ¼ cup (55 g) packed light brown sugar
- ¼ cup (50 g) granulated sugar
- 1 ½ teaspoons ground cinnamon
- ⅛ teaspoon kosher salt
- 6 tablespoons (84 g) unsalted butter, melted and cooled
For the filling
- 4 ½ pounds sweet potatoes, (5 to 6 large sweet potatoes)
- ¼ cup (50 g) granulated sugar
- ¼ teaspoon kosher salt
- ½ cup (4 fluid ounces) milk
- 4 (200 g (weighed out of shell)) eggs, lightly beaten
- 5 tablespoons (70 g) unsalted butter, melted and cooled
- ½ teaspoon vanilla extract
Instructions
Make the crumble topping.
- in a medium-sized bowl, place the flour blend, xanthan gum, oats, brown sugar, granulated sugar, cinnamon, and salt, and whisk to combine, working out any lumps in the brown sugar.
- Add the melted butter, and mix to combine well. The mixture will be thick.
- Place the bowl in the refrigerator to chill until firm (at least 10 minutes and up to 3 days).
Roast the sweet potatoes
- Preheat your oven to 375°F. Wash and dry the raw sweet potatoes, then pierce all over with the tines of a fork. Wrap each separately in aluminum foil, place on a rimmed baking sheet.
- Bake until a paring knife inserted in the center of the thickest part of each sweet potato doesn’t encounter any resistance (45 minutes to 1 hour+, depending upon size).
- Remove the sweet potatoes from the oven, unwrap them, and allow them to cool until you’re able to handle them. Once roasted and skinned, your sweet potatoes should weigh at least 3 1/2 pounds.
- Reduce the oven temperature to 350°F. Grease a 9-inch x 12- or 13-inch baking dish and set it aside.
Make the filling
- In the bowl of a food processor fitted with the steel blade (See Recipe Notes), place the sweet potato flesh and process for about 2 minutes.
- With the food processor still working, add the remaining ingredients (granulated sugar, salt, milk, eggs, butter, and vanilla) through the shoot and process until smooth.
- Stop the food processor as necessary to scrap down the sides and keep the mixture moving. The filling will be thick but very soft and smooth.
Assemble the dish
- Transfer the filling to the prepared baking dish, and smooth the top into an even layer.
- Remove the crumble topping from the refrigerator, break it up into irregular pieces with the tines of a fork, and sprinkle the pieces evenly over the top of the filling.
Bake
- Place in the center of the preheated oven and bake until the topping is golden brown and the filling appears set (about 45 minutes). Allow the dish to cool completely before serving.
Video
Notes
You can replace the oats in the crumble topping recipe with flattened rice or buckwheat flakes. You can also just use an additional 1/4 cup (35 g) all purpose gluten free flour (for a total of 1 cup (140 g)). About the food processor
If you only have a small food processor, purée the sweet potatoes in batches, and then mix everything together in a large bowl. If you don’t have a food processor, I’ve made the filling with a hand mixer, but it’s just not as smooth.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Thanks so much!!
I forgot to add that I used vegan options to replace the dairy ingredients. I used Miyoko’s butter and Unsweetened Ripple .
Glad to know the Miyoko’s vegan butter worked so well. It and Melt brand vegan butters really are a big improvement over other butter substitutes. And Ripple is great, too (although I wish it weren’t so expensive). Well done, Corrin!