Why You’ll Love This Recipe

I love how simple this casserole is to prepare. The slow cooker gently cooks the sweet potatoes until they are tender, so I don’t need to boil them separately or use another baking dish.

I also enjoy the combination of textures and flavors. The sweet potato base is creamy and buttery, while cinnamon, nutmeg, and vanilla add warmth. Pecans provide a little crunch, and melted marshmallows create the sweet, gooey topping I expect from a traditional sweet potato casserole.

Ingredients

(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)

4 pounds sweet potatoes, peeled and cut into 1-inch cubes
½ cup unsalted butter, melted
½ cup packed brown sugar
¼ cup maple syrup
1 teaspoon ground cinnamon
¼ teaspoon ground nutmeg
½ teaspoon salt
1 teaspoon vanilla extract
½ cup milk
2 cups mini marshmallows
¾ cup chopped pecans

Directions

I lightly grease the inside of a 6-quart slow cooker to make serving and cleanup easier.
I peel the sweet potatoes and cut them into roughly 1-inch cubes. I try to keep the pieces similar in size so they cook evenly.
I place the cubed sweet potatoes in the slow cooker.
In a small bowl, I combine the melted butter, brown sugar, maple syrup, cinnamon, nutmeg, salt, and vanilla.
I pour the butter mixture over the sweet potatoes and gently toss until the pieces are evenly coated.
I cover the slow cooker and cook on HIGH for approximately 3 to 4 hours or on LOW for 6 to 7 hours, until the sweet potatoes are very tender when pierced with a fork.
Once tender, I mash the sweet potatoes directly in the slow cooker. I gradually stir in the milk until I reach the creamy consistency I like.
I smooth the sweet potato mixture into an even layer and sprinkle the chopped pecans over the top.
I scatter the mini marshmallows over the pecans, replace the lid, and cook on HIGH for another 10 to 15 minutes, or just until the marshmallows are soft and melted.
I serve the casserole warm directly from the slow cooker.

Servings and Timing

This recipe makes approximately 10 to 12 servings, which I find ideal for a holiday dinner or larger family gathering.

Prep time: 20 minutes
Cook time on HIGH: 3 to 4 hours
Cook time on LOW: 6 to 7 hours
Finishing time: 10 to 15 minutes
Total time: approximately 3 hours 30 minutes when cooked on HIGH
Servings: 10 to 12

I usually use the HIGH setting when preparing this casserole on the day of a holiday meal. When I have more time, I use LOW and allow the sweet potatoes to cook gently throughout the day.

Variations

For a pecan streusel version, I skip the marshmallows and combine chopped pecans with brown sugar, melted butter, and a little flour. I sprinkle the mixture over the cooked sweet potatoes before covering the slow cooker for the final few minutes.

When I want a less sweet casserole, I reduce the brown sugar and leave out the maple syrup. The natural sweetness of the potatoes still gives me plenty of flavor.

For extra richness, I replace the milk with half-and-half or heavy cream. I add it gradually so I can control the consistency of the casserole.

If I want more texture, I leave some of the sweet potatoes in small pieces rather than mashing them completely smooth.

I can also make a nut-free version by leaving out the pecans and using only marshmallows for the topping.

Storage/Reheating

I let leftover sweet potato casserole cool before transferring it to an airtight container. I store it in the refrigerator for up to 3 to 4 days.

For longer storage, I freeze the sweet potato portion in a freezer-safe container for up to about 3 months. I prefer freezing it without the marshmallow topping because fresh marshmallows give me a better texture after reheating.

To reheat a larger portion, I place the casserole in an oven-safe dish, cover it with foil, and warm it at 350°F (175°C) until heated through. I add fresh marshmallows near the end if needed. For individual portions, I reheat the casserole in the microwave in short intervals until hot.

FAQs

Can I use canned sweet potatoes for Slow Cooker Sweet Potato Casserole?

Yes, I can use canned sweet potatoes when I need a shortcut, but I drain them thoroughly first. Since they are already cooked, I significantly reduce the cooking time and heat them only until the ingredients are hot and well combined.

Can I prepare Slow Cooker Sweet Potato Casserole ahead of time?

Yes. I can prepare and mash the sweet potato mixture ahead of time, refrigerate it in an airtight container, and reheat it before serving. I prefer adding the pecans and marshmallows near the end so the topping has the best texture.

How do I keep the sweet potato casserole from becoming watery?

I avoid adding too much liquid at the beginning because the sweet potatoes release moisture as they cook. I add the milk only after the potatoes are tender and mashed, which lets me control the final consistency more easily.

Can I make this casserole without marshmallows?

Yes. When I don’t want marshmallows, I top the casserole with chopped pecans or a buttery pecan streusel. I can also serve the sweet potato mixture without any topping for a simpler side dish.

Can I keep Sweet Potato Casserole warm in the slow cooker?

Yes. Once the casserole is fully cooked, I can switch my slow cooker to the WARM setting for serving. I avoid leaving it on WARM for an excessive amount of time because the edges can eventually dry out or the marshmallow topping can become overly soft.

Conclusion

Slow Cooker Sweet Potato Casserole is one of my favorite ways to simplify a holiday meal while still serving a traditional, comforting side dish. I love the combination of creamy sweet potatoes, brown sugar, maple syrup, warm spices, crunchy pecans, and soft marshmallows.

Slow Cooker Sweet Potato Casserole Recipe

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A warm and comforting slow cooker sweet potato casserole with buttery sweet potatoes, brown sugar, maple syrup, warm spices, crunchy pecans, and gooey marshmallows. It is an easy holiday side dish that keeps valuable oven space free.

Author: Laura
Prep Time: 20 minutes
Cook Time: 3 hours 10 minutes
Total Time: 3 hours 30 minutes
Yield: 10 to 12 servings
Category: Side Dish
Method: Slow Cooker
Cuisine: American
Diet: Vegetarian

Instructions

Lightly grease the inside of a 6-quart slow cooker.
Peel the sweet potatoes and cut them into roughly 1-inch cubes, keeping the pieces similar in size for even cooking.
Place the cubed sweet potatoes in the slow cooker.
In a small bowl, combine the melted butter, brown sugar, maple syrup, cinnamon, nutmeg, salt, and vanilla.
Pour the butter mixture over the sweet potatoes and gently toss until evenly coated.
Cover and cook on HIGH for 3 to 4 hours or on LOW for 6 to 7 hours, until the sweet potatoes are very tender when pierced with a fork.
Mash the tender sweet potatoes directly in the slow cooker. Gradually stir in the milk until the desired creamy consistency is reached.
Smooth the sweet potato mixture into an even layer and sprinkle the chopped pecans over the top.
Scatter the mini marshmallows over the pecans. Cover and cook on HIGH for another 10 to 15 minutes, just until the marshmallows are soft and melted.
Serve the sweet potato casserole warm directly from the slow cooker.

Notes

For a pecan streusel variation, omit the marshmallows and top with a mixture of chopped pecans, brown sugar, melted butter, and a little flour.
For a less sweet casserole, reduce the brown sugar and omit the maple syrup.
For extra richness, replace the milk with half-and-half or heavy cream.
For more texture, leave some of the cooked sweet potatoes in small pieces instead of mashing them completely smooth.
For a nut-free version, omit the pecans and use only marshmallows as the topping.
Canned sweet potatoes can be used as a shortcut; drain thoroughly and significantly reduce the cooking time because they are already cooked.
Store leftovers in an airtight container in the refrigerator for 3 to 4 days.
The sweet potato mixture can be frozen without the marshmallow topping for up to 3 months.
For make-ahead preparation, refrigerate the mashed sweet potato mixture and add the pecans and marshmallows when reheating.
Once fully cooked, the casserole can be held briefly using the slow cooker’s WARM setting.

Nutrition

Serving Size: 1/12 of recipe
Calories: 350 kcal
Sugar: 27 g
Sodium: 150 mg
Fat: 15 g
Saturated Fat: 6 g
Unsaturated Fat: 8 g
Trans Fat: 0 g
Carbohydrates: 53 g
Fiber: 5 g
Protein: 4 g
Cholesterol: 22 mg