Healthy Sweet Potato Casserole, No Marshmallows Needed

This healthy sweet potato casserole keeps everything people love about the Thanksgiving classic: a soft, spiced, naturally sweet filling and a crunchy topping you have to fight for. What it drops is the cup of brown sugar, the stick of butter and the marshmallows. Greek yogurt makes the filling creamy, 5 tablespoons of maple syrup sweeten the whole dish, and a pecan oat crumble gives you the crunch. Each serving comes in at about 253 calories with 7.3 g protein and 5.3 g fiber.

It also makes your Thanksgiving easier. The filling can be made two days ahead, and the casserole bakes in the 30 minutes while the turkey rests.

Healthy Sweet Potato Casserole Ingredients

Serves: 8. Prep: 15 minutes. Roast and bake: about 1 1/2 hours. Dish: 8×8-inch or 2-quart baking dish (double everything for a 9×13).

For the sweet potato filling

• 3 1/2 lb (about 1.6 kg) sweet potatoes, 4 to 5 medium
• 2/3 cup (150 g) plain nonfat Greek yogurt
• 2 large eggs
• 3 tbsp (60 g) pure maple syrup
• 1 tsp vanilla extract
• 1 tsp ground cinnamon
• 1/4 tsp ground nutmeg
• 1/2 tsp salt

For the pecan oat crumble

• 1/2 cup (55 g) pecans, chopped
• 1/2 cup (40 g) old-fashioned rolled oats
• 2 tbsp (40 g) pure maple syrup
• 1 tbsp (14 g) butter, melted
• 1/2 tsp ground cinnamon

Use orange-fleshed sweet potatoes (the ones often labeled “yams” in US stores) for the classic color and the softest mash. Purple or white Japanese sweet potatoes work too, but they’re drier and starchier, so you may need an extra spoonful of yogurt. If you love those, our roasted Japanese sweet potatoes are the better way to show them off.

How to Make It

1. Heat the oven to 400°F. Prick the sweet potatoes with a fork, set them on a foil-lined baking sheet and roast until very soft, 50 to 60 minutes.
2. When they are cool enough to handle, scoop the flesh into a large bowl and discard the skins. You need about 4 cups (1,000 g).
3. Mash the sweet potatoes until smooth, then beat in the Greek yogurt, eggs, 3 tbsp maple syrup, vanilla, cinnamon, nutmeg and salt.
4. Lower the oven to 350°F and spread the filling in a greased 8×8-inch or 2-quart baking dish.
5. Stir the pecans, oats, 2 tbsp maple syrup, melted butter and cinnamon together in a small bowl, then scatter the crumble over the filling.
6. Bake uncovered for 30 to 35 minutes, until the edges bubble and the topping is golden. Let it rest for 10 minutes before serving.

Why roast instead of boil? Boiled sweet potatoes soak up water and give you a loose, bland filling. Roasting does the opposite: it drives off moisture and caramelizes the natural sugars, which is exactly why this casserole needs so little syrup. If you see sticky dark spots leaking onto the foil, that’s a good sign.

Let the yogurt come to room temperature for 20 minutes before mixing. Cold yogurt straight into hot potatoes can turn a little grainy.

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What Makes This Sweet Potato Casserole Healthier

Most classic recipes build the dish from three heavy layers: a filling loaded with sugar, butter and cream, a brown-sugar pecan streusel, and a blanket of marshmallows. Here is what changes in this version.

Part of the dish	Classic version	This version
Sweetener	Brown or white sugar, plus marshmallows	5 tbsp maple syrup for the whole dish
Creaminess	Butter and heavy cream or evaporated milk	Nonfat Greek yogurt
Topping	Brown sugar, flour and butter streusel	Pecans, rolled oats and 1 tbsp butter
Cooking the potatoes	Often boiled	Roasted for deeper natural sweetness

Greek yogurt in the filling. It does the job of butter and cream, adds a gentle tang that keeps the casserole from tasting like dessert, and brings protein: 10.2 g per 100 g according to USDA data. Together with the eggs, that’s where most of the 7.3 g protein per serving comes from.

Maple syrup instead of sugar. Roasted sweet potatoes are already sweet, so 3 tablespoons in the filling is plenty. Taste it before the eggs go in. If your potatoes were large and less sweet, add one more tablespoon.

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An oat and pecan crumble. Oats and pecans add fiber and the crunchy, toasty top that the marshmallows usually provide, with just one tablespoon of butter holding it together. I’ll be honest: I don’t miss the marshmallows, and the crumble stays crisp on leftovers, which marshmallows never do.

Calories and Nutrition per Serving

We calculated these from USDA FoodData Central values for each ingredient, based on 1,000 g of baked sweet potato flesh, and divided by 8. Vanilla, spices and salt aren’t counted. Sweet potatoes vary in size, so treat the numbers as close estimates.

Per serving (1/8 of the dish)	With crumble	Filling only
Calories	253	161
Protein	7.3 g	6 g
Carbs	39.4 g	31.7 g
Fat	8.2 g	1.5 g
Fiber	5.3 g	4.1 g

Most of the fat comes from the pecans, which is the kind of fat I’m happy to keep on a holiday plate. If you want the lightest version, bake the filling alone and scatter a small handful of toasted pecans over the top just before serving.

Make-Ahead Sweet Potato Casserole for Thanksgiving

This is one of the easiest sides to get done early, and it frees up the oven on the big day.

• Up to 2 days ahead: roast and mash the sweet potatoes, mix in everything for the filling, spread it in the baking dish, cover and refrigerate. Mix the crumble and keep it in a separate airtight container at room temperature so it stays crunchy.
• On Thanksgiving: take the dish out of the fridge 30 minutes before baking, add the crumble, and bake at 350°F for 40 to 45 minutes, since it starts cold.
• Leftovers: FoodSafety.gov’s cold food storage chart gives 3 to 4 days in the refrigerator for cooked leftovers, and that’s the window we use here. Reheat portions in the microwave or the whole dish at 325°F, loosely covered with foil.

Planning the whole table? Our healthy Thanksgiving sides with a day-by-day prep plan includes this casserole’s timing alongside the mashed potatoes, stuffing and green beans.

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Variations and Easy Swaps

• Still want marshmallows? Skip the crumble on half the dish and scatter mini marshmallows there for the last 5 minutes of baking. Kids get their marshmallow corner, and everyone else gets pecans. The nutrition numbers above won’t apply to that half.
• Nut-free: replace the pecans with pepitas (pumpkin seeds) or double the oats.
• Gluten-free: use oats labeled certified gluten-free.
• Dairy-free: use a thick unsweetened plain coconut or almond yogurt and swap the butter for coconut oil. The protein will be lower.
• Orange-scented: add the zest of one orange to the filling. It pairs well with cranberry sauce on the plate.
• Canned sweet potatoes: they work in a pinch. Use two 29 oz cans of sweet potatoes packed in water (not syrup), drain well, and skip the roasting step. The filling will be a little softer and less caramelized.

Is Sweet Potato Casserole Healthy?

It can be. Sweet potatoes themselves are a solid vegetable: USDA data lists baked sweet potato at 90 calories, 2 g protein and 3.3 g fiber per 100 g. What turns the classic casserole into a dessert is the added sugar, butter and marshmallows on top. Cut those back, roast the potatoes for flavor, and you get a side dish that still feels festive but sits much more comfortably next to turkey and a plate of greens.

Want more ways to use the rest of the bag? Our healthy sweet potato recipes beyond the casserole cover weeknight dinners and breakfasts. And for dessert, the healthy pumpkin pie with a press-in oat crust uses the same maple-and-oats idea and can be baked on Tuesday too. Once the holiday is over, turn the leftover bird into turkey soup from the carcass.

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Sweet potatoes are at their seasonal peak right now, and they show up on most November cooking lists, like Ambitious Kitchen’s 30 seasonal recipes to cook in November, which puts them alongside pumpkin and winter squash in its Thanksgiving prep.

Sources

• USDA FoodData Central values per 100 g, via GetFoodFacts: sweet potato, baked in skin (FDC 168483), nonfat Greek yogurt (FDC 170894), egg, whole, raw (FDC 171287), maple syrup (FDC 169661), pecans (FDC 170182), oats (FDC 173904), butter, salted (FDC 173410).
• Storage times: FoodSafety.gov, Cold Food Storage Chart.
• Seasonal context: Ambitious Kitchen, 30 Seasonal Recipes to Cook in November (published October 31, 2026).