Go Back
Sweet potatoes with melted marshmallows in a baking dish

Grandma's Classic Sweet Potato Casserole with Toasted Marshmallows

This classic sweet potato casserole features creamy mashed sweet potatoes topped with a golden, toasted marshmallow crust, perfect for any holiday gathering or family meal.
Print Recipe Pin Recipe
Prep Time 15 minutes
Cook Time 25 minutes
Total Time 40 minutes
Servings: 8 people
Calories: 450
Ingredients Equipment Method Notes

Ingredients
  

Main Ingredients
  • 3 pounds sweet potatoes
  • 1/2 cup unsalted butter
  • 1/4 cup packed brown sugar
  • 1/4 cup milk or cream
  • 1 teaspoon vanilla extract
  • 1/2 teaspoon cinnamon
  • 1/4 teaspoon salt
  • 4-5 cups mini marshmallows

Equipment

  • Large pot
  • Potato masher
  • 9x13-inch baking dish

Method
 

Preparation
  1. Peel and cut the sweet potatoes into 1-inch cubes.
  2. Place cubed sweet potatoes in a pot, cover with cold water, bring to a boil, then simmer for 15-20 minutes until tender. Drain well.
  3. Return the hot, drained sweet potatoes to the pot. Add butter, brown sugar, milk, vanilla extract, cinnamon, and salt. Mash until smooth and creamy, then adjust seasoning to taste.
  4. Spoon the mashed sweet potato mixture evenly into a 9x13-inch baking dish.
  5. Evenly layer the marshmallows over the sweet potato mixture.
  6. Preheat oven to 375°F (190°C). Bake for 20-25 minutes until heated through and marshmallows are golden and caramelized. Monitor marshmallows closely.
  7. Allow the casserole to cool for 5-10 minutes before serving.

Notes

For extra flavor, you can add a pinch of nutmeg or allspice to the sweet potato mixture. If using jumbo marshmallows, slice them in half for easier layering and melting.