This vegan and gluten-free sweet potato and butternut squash casserole is a savory alternative to the usual sweet potato casserole.
While it might be a bit old fashioned, I still love the idea of a casserole when the temperatures starts to drop. Especially around the holidays when time is short and there are lots of hungry mouths to feed, a warming casserole is always an easy and dependable addition to the table.
This make-ahead sweet potato butternut squash casserole is one of my go-to’s when I’m putting together my holiday menu. Yes it’s technically a sweet potato casserole, but it’s nothing like those sticky sweet marshmallow ones we’ve all come to associate with the holidays.
This warm and soothing casserole is a savory affair, no sugar or maple syrup or marshmallows in sight. It’s made gratin-style, which is simply the term for topping a dish with bread crumbs and/or cheese (or a mix) and baking until browned and crisp.
And while traditional gratins are typically made with lots of cream, butter, cheese; this one relies on the inherent silkiness of sweet potatoes and butternut squash, along with a dollop of dairy-free yogurt for extra creaminess and a simple almond and nutritional yeast based breadcrumb topping to deliver all the same satisfying richness.
How to make it:
Roasted sweet potatoes and butternut squash are blended together to create a purée, that’s then layered with the olive oil and thyme scented “breadcrumb” topping and baked until golden and bubbly. The result is a luxurious silky mash with an irresistibly salty, savory, “cheesy”, crisp crust.
Both the purée and topping can be made the day before and just popped in the oven at the last minute, making it a natural for the holiday table or any harried weeknight meal.
It’s s a tasty, savory way to enjoy your sweet potatoes this season.
More holiday sides:

Sweet Potato Butternut Squash Casserole
This thyme scented vegan and gluten-free sweet potato and butternut squash casserole is a savory alternative to the usual sweet potato casserole.
Ingredients
For the purée:
- 1 Tablespoon/15ml extra virgin olive oil, plus more for the dish
- 1 clove garlic, peeled and cut in half
- 2 small (or 1 large) sweet potatoes, scrubbed and pierced several times with the tines of a fork
- 1 small butternut squash, cut in half, seeds removed
- ½ teaspoon fine sea salt
- ⅛th teaspoon freshly ground black pepper
- ¼ cup/60ml coconut yogurt
For the topping:
- ½ cup/56g almond flour
- 2 Tablespoons/12 g tapioca flour
- 2 Tablespoons/10g nutritional yeast
- 2 Tablespoons/30ml extra virgin olive oil/ ml
- 2 Tablespoons fresh thyme leaves
- ¼ teaspoon fine sea salt
- Pinch of freshly ground black pepper
Instructions
- Heat oven to 400 degrees. Grease a 1 to 1 ½ quart gratin dish with olive oil and rub with cut garlic clove, set aside.
- Place sweet potatoes on a baking sheet and bake for 45 minutes to an hour or until tender when pierced with a knife.
- Rub cut butternut squash with olive oil and sprinkle with salt and pepper. Place butternut squash cut side down on a separate baking sheet. Bake for 45 minutes to an hour or until tender when pierced with a knife.
- Remove sweet potatoes and squash from the oven. Scoop out flesh and place in a food processor or high speed blender along with salt, pepper and yogurt and puree until smooth. You should have about 1lb to 1 ½ of purée. (Purée can be made a day ahead of time.)
- Combine topping ingredients in a bowl, set aside.
- Transfer sweet potato and pumpkin mixture to prepared dish, sprinkle “breadcrumb” topping over gratin.
- Transfer gratin dish to oven, and bake for about 20-25 minutes, or until topping is golden. Remove from oven and serve warm.
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Nutrition Information:
Yield:
4Serving Size:
1Amount Per Serving: Calories: 259Total Fat: 16gSaturated Fat: 2gTrans Fat: 0gUnsaturated Fat: 14gCholesterol: 0mgSodium: 279mgCarbohydrates: 25gFiber: 5gSugar: 4gProtein: 6g
Nutritional information for recipes contained on this website, such as calories, fat, carbs, etc. are only estimates and are not guaranteed to be accurate.
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Sylvie Shirazi is the recipe developer and food photographer behind Gourmande in the Kitchen. For the last 10 years she's been making eating more healthfully easy and accessible with gluten-free, grain-free, paleo and vegan recipes that are free from processed ingredients.
Charlotte says
Hi!
Just wondering if instead of baking the butternut and the sweet potato I could boil them?
My oven is not working well and the grill is the only option working well, I'm not sure how long it would take if I try baking them!
Thanks!
Charlotte
Sylvie says
Yes you can boil or steam them but the final dish will have less flavor.