Everyone goes crazy for this Sweet Potato Casserole with Marshmallows and Streusel! Mashed sweet potatoes topped with toasted marshmallows and a brown sugar-cinnamon-pecan streusel. The perfect side dish for Thanksgiving or any holiday celebration.
Prep Time 20 minutes | Cook Time 40 minutes | Total Time 1 hour 20 minutes
Mashed Sweet Potatoes:
- 3 pounds sweet potatoes* peeled and chopped into large chunks, see note
- 2 tablespoons unsalted butter
- 1/4 cup milk or half and half
- 1/2 teaspoon ground cinnamon or pumpkin pie spice
- 2 tablespoons brown sugar
- salt to taste
- 4 tablespoons unsalted butter softened
- 1/4 cup brown sugar
- 1/4 cup all purpose flour optional: for a sturdier streusel add and additional heaping tablespoon of flour
- 1/2 teaspoon ground cinnamon
- 1/8 teaspoon salt
- 1/2 cup chopped pecans
- 2 -3 cups mini marshmallows or more, if you’d like
- Preheat oven to 375°F. Grease a 2 or 2 1/2 quart casserole dish and set aside.
- Place the sweet potatoes in a large pot, cover with water, and boil until tender (about 7 minutes, depending on the size). Drain and return to the pot. Add butter, milk, cinnamon, brown sugar and salt to the potatoes and mash until smooth. Use a hand mixer, if desired, to make them extra smooth. Taste the potatoes and add additional seasonings, if desired.
- Transfer the mashed potatoes to the prepared casserole dish. Place in the oven until heated through (if they’re warm it will only take a few minutes).
- While the sweet potatoes are heating, prepare the topping. In a medium bowl, combine butter, brown sugar, flour, cinnamon, salt, and pecans. Stir until thoroughly combined.
- Remove the sweet potatoes from the oven. Top with half the marshmallows, then sprinkle half the streusel over the marshmallows. Top with the other half of the marshmallows and sprinkle the remaining streusel over the top. Place back into the oven for 8-15 minutes, until the topping is bubbly and brown (keep an eye on it so the marshmallows don’t burn). You can also place it under the broiler very briefly to add a little more color to the marshmallows.