Marshmallow Air Fryer Sweet Potato Casserole

I used to dread making sweet potato casserole every Thanksgiving because it meant heating up my whole kitchen with the oven running for hours. Plus, I could never get the timing right with everything else I was cooking.

Then I discovered you can make this holiday favorite in the air fryer. It cooks faster, doesn’t heat up your house, and honestly tastes just as good as the traditional version. The best part? You free up precious oven space for your turkey and other dishes.

What Kind of Sweet Potatoes Should I Use?

For this casserole, you’ll want to pick up orange-fleshed sweet potatoes, which are the most common variety you’ll find at the grocery store. These have that classic sweet, creamy texture that works perfectly for casseroles. You can use either the longer, tapered sweet potatoes or the shorter, rounder ones – both will give you great results. When selecting your sweet potatoes, look for ones that feel firm and heavy for their size, without any soft spots or wrinkled skin. Since you’ll be cooking them first before making the casserole, don’t worry too much about getting them all exactly the same size, just aim for large ones as the recipe calls for.

Options for Substitutions

This sweet potato casserole is pretty forgiving when it comes to swaps and substitutions:

• Sweet potatoes: You can use canned sweet potatoes (about 3 cups mashed) instead of fresh ones. Just drain them well and skip the cooking step. Butternut squash also works as a substitute, though it’ll give you a slightly different flavor.
• Brown sugar: If you’re out of brown sugar, mix ½ cup granulated sugar with 2 tablespoons molasses, or just use all granulated sugar for a lighter sweetness.
• Pecans: Walnuts, chopped almonds, or even crushed graham crackers make good substitutes. You can also skip the nuts entirely if you have allergies.
• All-purpose flour: For a gluten-free version, use almond flour or oat flour instead. You might need slightly less since these flours can be denser.
• Butter: Coconut oil (solid, not melted) works well in place of the cold butter for the topping. For the melted butter in the filling, you can use melted coconut oil or vegetable oil.
• Mini marshmallows: Regular marshmallows cut into pieces work just fine, or you can skip them altogether for a less sweet version. Some people like adding a streusel topping instead.

Watch Out for These Mistakes While Cooking

The biggest mistake when making air fryer sweet potato casserole is not cooking your sweet potatoes long enough beforehand – they need to be completely tender and mashable, or you’ll end up with lumpy, undercooked chunks in your final dish.

Another common error is adding the topping too early in the cooking process, which can cause your pecans to burn and marshmallows to turn black before the casserole is heated through – wait until the last 5-10 minutes to add these delicate toppings.

Make sure your sweet potato mixture is completely smooth before transferring to the air fryer basket, and don’t forget to check that your air fryer basket isn’t overcrowded, as this can lead to uneven cooking and soggy spots.

For best results, let the casserole rest for a few minutes after cooking so the flavors can settle and it’s easier to serve without falling apart.

What to Serve With Sweet Potato Casserole?

Sweet potato casserole is a natural fit for your Thanksgiving table, but it pairs beautifully with so many other meals too! I love serving it alongside roasted turkey, glazed ham, or even simple grilled chicken for a cozy weeknight dinner. The sweet and nutty flavors work really well with savory green bean casserole, stuffing, and cranberry sauce if you’re going full holiday mode. For a lighter approach, try it with a crisp fall salad with apples and walnuts, or some roasted Brussels sprouts to balance out all that sweetness.

Storage Instructions

Refrigerate: Sweet potato casserole keeps really well in the fridge for up to 5 days when covered tightly with foil or plastic wrap. I actually think it tastes even better the next day because all those flavors have time to meld together. Just make sure it’s completely cooled before covering to avoid condensation.

Freeze: This casserole freezes like a dream for up to 3 months! You can freeze it before or after baking – just wrap it really well in plastic wrap and then foil. If you’re freezing it unbaked, add about 15-20 extra minutes to the cooking time when you’re ready to make it.

Warm Up: To bring back that fresh-from-the-air-fryer taste, cover with foil and warm it in a 350°F oven for about 15-20 minutes until heated through. If you want those marshmallows nice and toasty again, remove the foil for the last 5 minutes. You can also reheat individual portions in the microwave for about 1-2 minutes.

Preparation Time	15-20 minutes
Cooking Time	10-14 minutes
Total Time	25-34 minutes
Level of Difficulty	Easy

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 2000-2200
• Protein: 30-40 g
• Fat: 90-110 g
• Carbohydrates: 300-320 g

Ingredients

For the topping:

• 1/2 cup white sugar
• 1/2 cup packed brown sugar
• 1/2 cup all-purpose flour
• 1 tsp ground cinnamon (optional)
• 1/4 cup unsalted butter, cold and cubed
• 1/2 cup pecans, chopped

For the sweet potato layer:

• 4 large sweet potatoes, cooked (baked, boiled, or air fried)
• 1/2 cup white sugar
• 2 large eggs
• 1 tsp vanilla extract
• 1/2 cup unsalted butter, melted
• 1/2 cup pecans, roughly chopped

For serving (optional):

• 2 cups mini marshmallows (vegetarian)

Step 1: Prepare the Streusel Topping

• 1/2 cup white sugar
• 1/2 cup packed brown sugar
• 1/2 cup all-purpose flour
• 1 tsp ground cinnamon (optional)
• 1/4 cup unsalted butter, cold and cubed
• 1/2 cup pecans, chopped

In a large bowl, combine the white sugar, brown sugar, all-purpose flour, and cinnamon (if using).

Add the cold, cubed unsalted butter and use a fork or pastry cutter to cut the butter into the dry mixture until it resembles coarse crumbs.

Stir in the chopped pecans to evenly distribute them throughout the topping.

Step 2: Cook the Sweet Potatoes

• 4 large sweet potatoes, cooked (baked, boiled, or air fried)

Cook the sweet potatoes by either baking, boiling, or air frying them until fully tender.

Once cooked, let them cool slightly before handling.

Personally, I like to bake them for a deeper, richer flavor, but boiling works great too if you’re short on time.

Step 3: Prepare the Sweet Potato Filling

• cooked sweet potatoes from Step 2
• 1/2 cup white sugar
• 2 large eggs
• 1 tsp vanilla extract
• 1/2 cup unsalted butter, melted
• 1/4 cup pecans, roughly chopped

Place the cooked sweet potatoes from Step 2 in a large mixing bowl.

Add the white sugar, eggs, vanilla extract, and melted butter.

Using a handheld mixer or potato masher, beat or mash the mixture until it’s smooth and fluffy.

Gently fold in 1/4 cup of the roughly chopped pecans to add some texture.

Step 4: Assemble and Bake the Casserole

• sweet potato filling from Step 3
• streusel topping from Step 1
• 1/4 cup pecans, roughly chopped (remaining)
• 2 cups mini marshmallows (vegetarian) (optional)

Grease an 8″ x 8″ baking dish that fits your air fryer and preheat the air fryer to 350°F (175°C).

Spread the sweet potato filling from Step 3 evenly in the prepared dish.

Scatter the streusel topping from Step 1 evenly over the sweet potato mixture.

Sprinkle the remaining 1/4 cup of roughly chopped pecans on top.

If you prefer extra sweetness or a festive touch, add mini marshmallows over the top.

Step 5: Bake and Serve

Place the assembled casserole in the air fryer and bake at 350°F (175°C) for 10–14 minutes, or until the topping is browned and the marshmallows are golden (if used).

Remove the casserole from the air fryer and let it cool slightly before serving warm and gooey.

I like to serve this dish right away while the marshmallows are melty and the topping is crisp.