Can I prep sweet potato casserole the night before?

Definitely. Cut the sweet potatoes and toss them in the sauce the night before. Store them in the fridge in a ziploc bag. The next day, just dump the potatoes in the slow cooker, and you’re ready to cook!

Can I make this recipe for a large crowd?

Yes, there should be plenty of room in your slow cooker, so you can easily double the recipe if you have more guests.

What if I don’t have pumpkin pie spice?

You can replace the pumpkin pie spice with 1/2 teaspoon each of cinnamon, nutmeg, and allspice instead!

Can I use canned sweet potatoes for this recipe?

We would not recommend this swap since canned sweet potatoes are already cooked, and many also are already sweetened. Additionally, pureed, canned sweet potatoes have a much different texture than cubed sweet potatoes.

Kitchen Tested

Slow-Cooker Sweet Potato Casserole

Name: Slow-Cooker Sweet Potato Casserole
Prep time: 20 min
Total time: 3 h 50 min
Yield: 14
Ingredients: 3/4 cup packed brown sugar; 2 tablespoons butter; 1 tablespoon pumpkin pie spice; 1 teaspoon salt; 1 tablespoon water; 1 tablespoon vanilla; 3 1/2 lb sweet potatoes, peeled and diced into 1/2-inch cubes; 2 cups miniature marshmallows

Prep time:20 min
Total time:3 hr 50 min
Ingredients:8
Servings:14
Calories per serving:190

By Created by Joanna(Opens in a new tab)Updated 07/24/2025

Slow-Cooker Sweet Potato Casserole

Prep time:20 min
Total time:3 hr 50 min
Ingredients:8
Servings:14
Calories per serving:190

This slow cooker sweet potato casserole is the perfect holiday side dish when stove and oven space is precious. The slow cooker makes for easy prep and hands-off cooking, so you can focus on the big showstoppers like the turkey and pies. And don't worry, our sweet potato casserole slow cooker recipe still calls for one of the best parts of the classic version: the marshmallow topping!

Sweet potatoes and marshmallows are a tried-and-true combination, especially around Thanksgiving—but have you ever wondered how that unlikely pairing came to be? While candied sweet potatoes were being made in America as early as the 1800s, it wasn’t until the turn of the 20th century that the company Angelus Marshmallows promoted a sweet potato casserole recipe using marshmallows as a topping as a way to sell their product—and it picked up steam from there. These days, you’ll have a hard time finding a table in the United States that doesn’t serve this unique dish on Thanksgiving.

First time making sweet potatoes? This slow cooker sweet potato casserole recipe is foolproof, but if you have any questions or want to learn more before you get started, check out our simple how-to guide.

Recipe Ingredients

Sweet potato casserole is such a cozy, crowd-pleasing side dish! Here’s what you’ll need to make it in your slow cooker.

Sweet Potatoes: We love cooking with sweet potatoes, because they’re naturally sweet, rich, and creamy. They’re the perfect base for the warm spices, brown sugar, and buttery toppings that make the holiday season so special.

Brown Sugar: This adds a deeper, richer flavor than white sugar—thanks to its molasses content—and enhances the natural sweetness of the sweet potatoes.

Pumpkin Pie Spice: Not only is this spice combo easy to find at grocery stores, but its irresistible seasonal flavor also sets this recipe apart from other traditional sweet potato casseroles.

Other Ingredients: We add butter for richness and marshmallows because it wouldn’t be a sweet potato casserole without them! A little salt to balance the sweet, plus vanilla to bring depth to all the flavors, and this casserole is ready to go.

How to Make Slow Cooker Sweet Potato Casserole

This slow cooker sweet potato casserole couldn’t be easier to make. Just follow a few simple steps, and you’ll have a delicious side dish with next-to-no effort. Here’s a quick overview—but check out the full list of ingredients and directions below.

1. Season the Potatoes

Start by melting together brown sugar, butter, pumpkin pie spice, salt, and a splash of water in the microwave to create a rich, spiced sauce. Stir in vanilla to add depth, then toss cubed sweet potatoes with the sauce until they’re thoroughly coated.

2. Transfer to the Slow Cooker

Add the sauced potatoes to your slow cooker, and cook on high for a few hours until the sweet potatoes are tender and full of flavor.

3. Add the Marshmallows

Just before serving, top the potatoes with marshmallows and briefly cover with the slow-cooker lid until they’re soft and slightly melted.

This slow cooker sweet potato casserole is the perfect holiday side dish to bring to parties, too. Start the cooking process at home, and once the potatoes are cooked, just bring the whole slow cooker with you! When you arrive, set it to warm, and add the marshmallows right before it’s time to eat.

Storing and Reheating

Got leftover sweet potato casserole? Don’t let it go to waste! Here’s how to keep it fresh.

Refrigerator

Store in an airtight container in the fridge for up to 3 days. We wouldn’t recommend storing your leftover casserole in the freezer as it won’t thaw and reheat well.

Reheating

Microwave individual servings for 1 to 2 minutes until heated through. Then, add a few more marshmallows to the top. The residual heat will melt them perfectly.

Frequently Asked Questions