This Slow Cooker Sweet Potato Casserole is the classic holiday side made the easy way, with spiced sweet potatoes mashed together with brown sugar, honey, and butter, then finished with a layer of gooey marshmallows and crunchy pecans. It has all the flavor of the traditional baked version, and it cooks from start to finish in the slow cooker.
It's rich, creamy, and exactly what everyone hopes to see on the Thanksgiving table.
I make this every Thanksgiving because it takes one of the biggest hosting headaches out of the way. Oven space is always the first thing to run out on a holiday, and this casserole doesn't need any of it. I get the sweet potatoes going in the slow cooker in the morning, give them one stir partway through, and then the oven is all mine for things like a pan of my Gluten-Free Stuffing, another classic Thanksgiving side.
It's also my favorite dish to bring when someone else is hosting. I make it at home, carry the whole slow cooker over, plug it in, and switch it to warm so it's ready right when the rest of the meal is. Nobody has to give up a burner or an oven rack for me, and it stays warm on the buffet while people go back for seconds.
If you love the fall flavors in this recipe, my Gluten-Free Sweet Potato Casserole and Roasted Sweet Potatoes are two more easy ways to get sweet potatoes on the table. Full gluten free Thanksgiving ideas to complete your table.
Ingredients Needed
I highly recommend fresh sweet potatoes for this recipe, though you can use canned or frozen if that's what you have. Peel them completely before cubing, since the skin turns chewy in the slow cooker and won't mash smoothly.
Honey and maple syrup are interchangeable here, so use whichever one you already have in the pantry, and I always reach for pure vanilla extract instead of imitation.
If you don't have pumpkin pie spice, you can mix your own with ground cinnamon, ginger, nutmeg, and a pinch of cloves. Use mini marshmallows rather than the large ones, since they melt evenly in the short time they're in the slow cooker.
Pecan halves are my favorite for the topping, but walnuts or almonds work just as well. The casserole is already plenty sweet, but candied nuts are another easy swap if you'd like.
See recipe card for quantities.
Instructions for Slow Cooker Sweet Potato Casserole
Add the sweet potatoes to the slow cooker
Cut the peeled sweet potatoes into 1-inch cubes, keeping them as even as you can so they all turn tender at the same time. Then add them to the slow cooker.
Pour in the brown sugar mixture
In a bowl, stir together the brown sugar, honey or maple syrup, melted butter, water, vanilla, pumpkin pie spice, cinnamon, and salt. Pour over the sweet potatoes and fold until every cube is coated.
Cook until tender
Cover and cook on HIGH for 3 to 4 hours or LOW for 6 to 8 hours until a fork slides easily into the sweet potatoes. Give everything a stir about halfway through so the potatoes heat evenly, and the edges don't burn.
Mash and smooth it out
Mash the sweet potatoes right in the slow cooker until smooth, then spread them into an even layer.
Add the marshmallows and pecans
Scatter the marshmallows and pecans over the top. Put the lid back on and cook for about 15 more minutes until the marshmallows have melted.
Toast the top and serve
If you have a kitchen torch or heat gun, you can brown the tops of the marshmallows for a little color and texture. The top gets toasty while the marshmallows underneath stay gooey. Serve it warm.
Variations
If variations have been incorporated into the Ingredients section, this section can become How to Serve. Variations can be written in bullet form with bold main ideas as shown below. How To Serve should be written in paragraph form and is a good place to incorporate internal links, especially if they were not used in the supporting paragraphs after the hero image.
- Chunky Candied Style: Skip the mashing and keep the sweet potatoes cubed. Add the marshmallows and pecans on top once the cubes are tender.
- Marshmallow Swirl: Stir some of the marshmallows and pecans into the mashed sweet potatoes, then top with the rest.
- No Marshmallows: Leave the marshmallows off and add extra pecans for a crunchy topping.
Equipment
I use a 6-quart slow cooker for this recipe, which fits all 4 pounds of sweet potatoes with room to stir halfway through.
A potato masher works great for mashing right in the slow cooker, or you can use a hand mixer if you like your sweet potatoes extra smooth.
For toasting the marshmallows, I like a small kitchen torch. It lets you brown the tops exactly where you want without heating the whole dish.
Storage and Reheating
Store leftovers in an airtight container in the refrigerator for up to 4 days. Reheat single servings in the microwave, or warm a larger amount in a covered dish in the oven until heated through.
The marshmallows soften and deflate once they've been refrigerated, so I like to add a handful of fresh marshmallows and pecans when I reheat.
The mashed sweet potatoes freeze well for up to 2 months, but the marshmallow topping doesn't hold up in the freezer. If you plan to freeze some, set it aside before adding the toppings.
Pro Tips
- If you're bringing this to someone else's house, hold off on the marshmallows and pecans until you get there. Plug in the slow cooker, switch it to HIGH to add the toppings, then turn it back to warm until dinner is served.
- Grease the slow cooker insert or use a slow cooker liner before adding the sweet potatoes.
- Toast the pecans in a dry skillet for a few minutes before adding them.
- Peel and cube the sweet potatoes the night before, then store them covered in cold water in the refrigerator. Drain and pat them dry before adding them to the slow cooker.
FAQ
No, the raw cubes cook until tender right in the slow cooker. Boiling sweet potatoes first makes them soak up water, which comes back out as they cook and can leave the casserole loose and watery.
Sure! Cook and mash the sweet potatoes a day ahead, then refrigerate them. When you're ready to serve, rewarm them in the slow cooker until heated through, stirring once or twice. Then add the marshmallows and pecans and cook until the marshmallows melt.
It holds well on warm for about 2 hours. That gives you plenty of time to get the rest of the meal on the table.
More Thanksgiving Recipes
Looking for other incredible Thanksgiving recipes like this? Try these:
Slow Cooker Sweet Potato Casserole
Ingredients
- 4 lbs sweet potatoes peeled and cut into 1-inch cubes
- ½ cup brown sugar
- ¼ cup honey or maple syrup
- ¼ cup butter melted
- 1 Tablespoon water
- ½ Tablespoon pure vanilla extract
- ½ Tablespoon pumpkin pie spice
- 1 teaspoon ground cinnamon
- ½ teaspoon salt
- 2 cups mini marshmallows
- ¾ cup pecan halves
Instructions
- Place the sweet potatoes in a 6-quart slow cooker.
- In a bowl, combine the brown sugar, honey, butter, water, vanilla, pumpkin pie spice, cinnamon, and salt. Pour over the sweet potatoes and fold to coat.
- Cover and cook on HIGH for 3-4 hours or LOW for 6-8 hours, stirring halfway through, until tender.
- Mash until smooth and spread into an even layer.
- Top with the marshmallows and pecans.
- Cover and cook for 15 minutes more, until the marshmallows melt.
- If desired, brown the marshmallows with a kitchen torch or heat gun.
Notes
Nutrition
Nutrition Disclaimer
All nutritional information provided is an estimate. For specific dietary needs or concerns, we recommend consulting a nutrition calculator or a qualified expert.
Karen Kelly
Karen Kelly is a nationally syndicated food and travel writer, founder of Seasonal Cravings, and co-founder of The Roam Report. She develops approachable seasonal recipes and covers travel and lifestyle trends. Her work has appeared in numerous media outlets, including Yahoo, Taste of Home, Apple News, NBC, FOX, and other national and regional publications.
Tell Us What You Think