This Sweet Potato Casserole with Marshmallows is creamy, buttery, and topped with golden toasted marshmallows. It is easy to make and always feels special. The sweet potatoes stay soft and smooth, while the marshmallows turn gooey with a lightly crisp top. This is one of those recipes that fills the kitchen with an amazing smell and disappears fast at the table.
Why I Love This Recipe
I started making this casserole years ago because I wanted something simple that still felt comforting. The first time I pulled it from the oven, the marshmallows puffed up into a golden blanket, and everyone gathered around before it even reached the table. Since then, it has become one of my favorite dishes whenever I want something warm and cozy.
What I love most is that it uses simple pantry ingredients, comes together without much work, and always gets compliments. It is sweet enough to feel like a dessert but still fits right alongside dinner.
- Rich, creamy sweet potato filling
- Soft, gooey marshmallow topping
- Easy ingredients you can find anywhere
- Great for holidays or family dinners
- Can be made ahead to save time
Servings and Time
- Servings: 8
- Prep Time: 20 minutes
- Cook Time: 35 minutes
- Total Time: 55 minutes
What You’ll Need
Ingredients
- 3 pounds sweet potatoes, peeled and cut into 1-inch cubes
- ½ cup unsalted butter, melted
- ⅓ cup brown sugar
- ¼ cup whole milk
- 2 large eggs
- 1 teaspoon vanilla extract
- ½ teaspoon salt
- ½ teaspoon ground cinnamon
- ¼ teaspoon ground nutmeg
- 3 cups mini marshmallows
Tools
- Large pot
- Colander
- Potato masher or hand mixer
- Large mixing bowl
- Measuring cups
- Measuring spoons
- Rubber spatula
- 9×13-inch baking dish
- Oven
Pro Tips
- Boil the sweet potatoes until a fork slides in easily. This makes the filling extra smooth.
- Mash while the potatoes are still hot so they blend better.
- Spread the marshmallows into one even layer so every bite gets some.
- Watch the casserole closely during the last few minutes because marshmallows brown quickly.
Substitutions and Variations
- Use half-and-half instead of whole milk.
- Add ½ teaspoon pumpkin pie spice instead of cinnamon and nutmeg.
- Mix chopped pecans into the filling or sprinkle them over the marshmallows.
- Use large marshmallows if mini marshmallows are unavailable. Cut them in half for more even coverage.
Make Ahead Tips
- Prepare the sweet potato filling one day ahead.
- Store it covered in the refrigerator.
- Add the marshmallows just before baking.
- Bake as directed, adding 5 extra minutes if starting cold.
Why This Recipe Works (Quick Science)
Sweet potatoes are full of natural starch. As they cook, the starch softens and makes the potatoes creamy. Butter adds richness, while milk keeps the mixture smooth. Eggs help hold everything together as the casserole bakes. Marshmallows contain sugar and gelatin, so they puff up, melt, and lightly brown on top, creating a soft, gooey layer.
Recipe
Step 1: Cook the Sweet Potatoes
Place 3 pounds of peeled, 1-inch sweet potato cubes into a large pot and cover them with cold water by about 1 inch. Bring to a boil over medium-high heat. Cook for 15 to 20 minutes, or until the sweet potato cubes are fork tender. Drain well in a colander and let them sit for 2 minutes so extra moisture can drain away.
Step 2: Mash and Mix
Transfer the hot drained sweet potato cubes to a large mixing bowl. Add ½ cup melted unsalted butter, ⅓ cup brown sugar, ¼ cup whole milk, 2 eggs, 1 teaspoon vanilla extract, ½ teaspoon salt, ½ teaspoon ground cinnamon, and ¼ teaspoon ground nutmeg. Mash until smooth and creamy with no large pieces remaining.
Step 3: Fill the Baking Dish
Spread the creamy sweet potato mixture evenly into a greased 9×13-inch baking dish using a rubber spatula. Smooth the top so the marshmallows will bake evenly.
Step 4: Add the Marshmallows
Sprinkle 3 cups of mini marshmallows evenly over the entire surface of the sweet potato mixture, making one complete layer.
Step 5: Bake
Bake at 350°F for 20 to 25 minutes, until the marshmallows are puffed, melted, and golden brown around the edges. Let the casserole rest for 5 minutes before serving.
Macros Information
Approximate per serving
- Calories: 345
- Protein: 5g
- Carbohydrates: 56g
- Fat: 12g
- Fiber: 5g
- Sugar: 30g
- Sodium: 245mg
Common Mistakes
- Do not undercook the sweet potatoes. They should mash easily.
- Drain the potatoes well so the casserole is not watery.
- Do not overmix after adding the eggs. Mix just until smooth.
- Do not add the marshmallows too early if making ahead.
- Watch the casserole closely near the end because marshmallows brown fast.
What to Serve With
- Roast turkey
- Baked ham
- Roast chicken
- Green beans
- Brussels sprouts
- Cranberry sauce
- Dinner rolls
- Fresh salad
Leftovers and Storage
- Cool completely before storing.
- Refrigerate in an airtight container for up to 4 days.
- Reheat in a 325°F oven until warm.
- Microwave individual portions for about 1 minute.
- Freeze without the marshmallow topping for up to 2 months. Add fresh marshmallows before baking after thawing.
FAQ
Q: Can I make this casserole ahead of time?
A: Yes. Make the filling up to one day ahead, cover it, refrigerate it, then add the marshmallows before baking.
Q: Can I use canned sweet potatoes?
A: Yes. Drain them very well and reduce the brown sugar slightly because canned sweet potatoes are often packed in syrup.
Q: Can I add pecans?
A: Yes. Stir chopped pecans into the filling or sprinkle them over the marshmallows before baking.
Q: Why is my casserole watery?
A: The sweet potatoes probably were not drained well enough after boiling.
Q: Can I freeze leftovers?
A: Yes. Freeze the sweet potato filling without marshmallows for the best texture.
Final Thoughts
This Sweet Potato Casserole with Marshmallows is creamy, rich, and full of comforting flavor. It is easy enough for a weeknight meal and special enough for holiday gatherings. The smooth sweet potatoes and toasted marshmallow topping make every bite warm and satisfying. Give it a try, then come back and leave a comment to share how it turned out or ask any questions. Happy cooking!