Slow-Cooker Sweet Potato Casserole with Marshmallows Tips, FAQ & printable recipe

Tips for success

For a smoother, more velvety texture, use an electric hand mixer on low speed to mash the sweet potatoes. Be careful not to overmix, which can make them gummy.

If you prefer a chunkier casserole, mash only lightly with a fork or potato masher. The brown sugar can be adjusted to taste; if your sweet potatoes are very sweet, reduce the sugar slightly.

The candied pecans are what give this dish its signature crunch. If they are not available, make a quick version by tossing chopped pecans with a little maple syrup and brown sugar, then toasting them in a skillet until caramelized.

You can also use regular toasted pecans for a less sweet topping. For a more decadent finish, dot the top with a few pats of butter before adding the marshmallows.

Variations

• Maple-Bourbon Sweet Potato Casserole: Replace the vanilla extract with 1 tablespoon of bourbon and swap the brown sugar for 1/2 cup of maple syrup. The bourbon adds a smoky depth, and the maple syrup complements the sweet potatoes beautifully.
• Pecan Streusel Topping: Instead of marshmallows, mix 1/2 cup all-purpose flour, 1/2 cup brown sugar, 1/2 cup cold butter, and 1 cup chopped pecans. Sprinkle over the mashed sweet potatoes and cook on HIGH for 15 minutes until the streusel is golden and crisp.
• Orange-Spiced Sweet Potato Casserole: Add 1 tablespoon of orange zest and 2 tablespoons of orange juice to the sweet potato mixture before cooking. The citrus brightens the flavor and pairs well with the cinnamon and nutmeg.
• Coconut-Marshmallow Topping: Mix 1/2 cup of toasted shredded coconut with the mini marshmallows before sprinkling over the top. The coconut adds a chewy texture and a tropical note that complements the sweet potatoes.

Storage and make-ahead

Fridge

Store leftovers in an airtight container in the refrigerator for up to 4 days. The marshmallows will soften but the casserole will still taste delicious.

Freezer

Freeze the casserole without the marshmallow topping for up to 3 months.

Reheat

Reheat individual portions in the microwave for 1–2 minutes or in a 350°F oven for 10–15 minutes.

Store leftover sweet potato casserole in an airtight container in the refrigerator for up to 4 days. The marshmallows will soften and may lose some of their toasted texture, but the flavor will remain.

Reheat individual portions in the microwave or in a 350°F oven until warmed through. Stir gently before serving to redistribute the topping.

This casserole can be assembled up to a day in advance. Cube the sweet potatoes and place them in the slow cooker insert with the brown sugar, butter, vanilla, cinnamon, and nutmeg. Cover and refrigerate overnight.

In the morning, set the slow cooker to HIGH and cook as directed, adding the marshmallows and pecans during the last 15 minutes. The topping should always be added at the end so it stays gooey and does not dissolve into the potatoes.

Serving ideas

Serve this sweet potato casserole warm, straight from the slow cooker, so the marshmallows are still soft and stretchy. Scoop it onto plates alongside roasted turkey, ham, or any holiday main. The contrast between the creamy, spiced potatoes and the sweet, crunchy topping makes it a crowd-pleaser that disappears quickly.

For a festive presentation, transfer the casserole to a serving dish and garnish with a few extra candied pecans and a sprinkle of cinnamon. It also pairs well with green beans, cranberry sauce, and dinner rolls. Leftovers can be enjoyed the next day, cold or reheated, as a sweet side dish or even a dessert-like treat.

Frequently asked questions

Recipe card

Slow-Cooker Sweet Potato Casserole with Marshmallows

Prep 15 minCook 3 h 45 minTotal 4 hServes 10

Ingredients

• 4 lb peeled and cubed sweet potatoes
• 1/2 cup packed brown sugar
• 1/2 cup melted butter
• 1 tsp vanilla extract
• 1 tsp ground cinnamon
• 1/4 tsp ground nutmeg
• 2 cups mini marshmallows
• 1/2 cup candied pecans

Instructions

1. Place the cubed sweet potatoes in a 6-quart slow cooker. Add the brown sugar, melted butter, vanilla extract, cinnamon, and nutmeg. Stir gently to coat every cube evenly.
2. Cover the slow cooker and cook on HIGH for 3 1/2 hours, or until the sweet potatoes are very tender when pierced with a fork. Stir once halfway through if possible.
3. Turn off the slow cooker. Mash the sweet potatoes right in the pot with a potato masher or wooden spoon until smooth and creamy. Scrape down the sides so everything is well combined.
4. Sprinkle the mini marshmallows evenly over the mashed sweet potatoes. Scatter the candied pecans over the marshmallows.
5. Cover the slow cooker and cook on HIGH for 15 more minutes, just until the marshmallows are puffed and golden. Watch closely so they do not burn.

Contains: milk, tree nuts

Estimated nutrition per serving

Calories

320

Protein

3 g

Carbohydrates

55 g

Fat

11 g

Automatic estimate from the ingredient list, not laboratory-verified.