Sweet Potato Casserole with Pecan Streusel and Marshmallows

Sweet Potato Casserole with pecan crumble and toasted marshmallows – buttery, creamy, not overly sweet, and perfect for a holiday side dish.

Sweet Potato Casserole is a holiday staple that brings together creamy, buttery mashed sweet potatoes with just the right touch of richness.

This recipe balances savoury and sweet by skipping extra sugar in the base, letting the natural flavour of the potatoes shine. A crisp pecan crumble topping adds crunch, while a layer of golden, toasted marshmallows gives it that classic festive finish.

Perfect for Thanksgiving or Christmas, this casserole is hearty, comforting, and guaranteed to be a crowd-pleaser at the holiday table.

Tips for Best Results

• Cut the potatoes into chunks: Roughly chopping the sweet potatoes before boiling helps them cook more quickly and evenly.
• Try roasting for extra flavour: Instead of boiling, you can roast the peeled, chopped sweet potatoes at 400°F (200°C) for 30–35 minutes, until tender. This brings out a deeper, caramelised flavour.
• Drain well (if boiling): After boiling, be sure to drain the potatoes thoroughly so the mash isn’t watery.
• Mash until smooth: Use a hand masher or electric mixer to get a creamy consistency before adding eggs and vanilla.
• Don’t skimp on the topping: The buttery pecan crumble adds texture and keeps the casserole from being too soft.
• Add marshmallows at the end: Wait until the last few minutes of baking to add marshmallows so they toast perfectly without burning.
• Serve warm: This casserole is best enjoyed fresh from the oven while the topping is crisp and the marshmallows are gooey.

Make-Ahead and Reheating Tips

• Assemble ahead: Prepare the sweet potato base and the pecan crumble separately. Store both in the fridge for up to 2 days. When ready to bake, spread the potatoes in the dish, add the crumble, and bake as directed. Add marshmallows just before serving.
• Bake and reheat: You can bake the casserole without marshmallows, cool completely, cover tightly, and refrigerate for up to 2 days. Reheat at 350°F (175°C) for 20–25 minutes, then top with marshmallows and bake for 8–10 minutes until golden.
• Freezing: For longer storage, assemble the casserole without marshmallows, wrap well, and freeze for up to 2 months. Thaw overnight in the fridge before baking.
• Serving leftovers: Reheat individual portions in the microwave or cover the dish with foil and warm in the oven at 325°F (165°C) until heated through.

Ingredients and Substitutions

• Sweet potatoes: Use orange-fleshed sweet potatoes for the best flavour and texture.
• Butter: Adds richness and flavour. Salted or unsalted butter both work – if using salted, reduce added salt slightly.
• Sour cream: Brings creaminess with a hint of tang. You can swap with Greek yogurt for a similar effect.
• Eggs: Help bind the casserole and give it structure. If you need an egg-free option, you can just skip the eggs, though the texture will be softer.
• Vanilla extract: Adds warmth and enhances the natural sweetness of the potatoes.
• Brown sugar: Sweetens the crumble and adds depth of flavour. Light or dark brown sugar both work, or you can use coconut sugar.
• Pecans: Give the topping a nutty crunch. Walnuts or almonds can be used as an alternative, or omit for a nut-free version.
• All-purpose flour: Helps bind the topping. Swap with oat flour or a gluten-free blend if needed.
• Mini marshmallows: Provide a gooey, sweet finish. You can skip them if you prefer only the pecan crumble.

Looking for More Festive Side Dishes?

Check out more of my favourite festive side dish recipes!

Enjoy fall flavours with this tasty roasted brussels sprouts and sweet potatoes recipe. Perfect for a weeknight meal or holiday feast!

A beautiful salad that’s perfect for fall, this Roasted Butternut Squash & Apple Salad recipe features candied pecans and feta cheese.

Roasted butternut squash with brown sugar and herbs is a tasty side dish for any fall menu. You will love this perfectly caramelized squash!

Sweet Potato Casserole with Pecan Streusel and Marshmallows

Yields: 10-12 servings | Prep time: 25 minutes | Cook time: 40-45 minutes

Ingredients:

Casserole Base

• 6 sweet potatoes
• ⅓ cup (75 g) butter
• ½ cup (120 g) sour cream
• 2 large eggs, beaten
• 1 teaspoon vanilla extract
• ½ teaspoon salt
• ¼ teaspoon black pepper

Crunch Topping

• ½ cup (100 g) brown sugar
• ¾ cup (90 g) chopped pecans
• 3 tablespoons (24 g) all-purpose flour
• 3 tablespoons (45 g) melted butter

Finishing

• 2 cups (about 100 g) mini marshmallows

Directions:

1. Peel sweet potatoes and roughly chop into large chunks. Place them into a large pot and cover with salted water. Bring to a boil, then reduce heat to medium-low and simmer until tender, about 20 to 30 minutes. Drain well.
2. Preheat oven to 375°F (190°C).

1. Mash the sweet potatoes with butter, sour cream, salt, and pepper. Beat in eggs and vanilla until smooth. Spread the mixture evenly into a greased 9×13-inch baking dish.

1. Make the topping: In a small bowl, stir together brown sugar, pecans, and flour. Mix in melted butter until crumbly. Sprinkle the topping evenly over the sweet potatoes.

1. Bake uncovered for 30–35 minutes, until hot and the topping is lightly browned.
2. Remove casserole from oven, sprinkle evenly with mini marshmallows, and return to oven for 8–10 minutes, until marshmallows are puffed and golden.

Continue to Content

Yield: 10-12 Servings

Sweet Potato Casserole with Pecan Streusel and Marshmallows

Prep Time: 25 minutes

Cook Time: 45 minutes

Total Time: 1 hour 10 minutes

Sweet Potato Casserole with pecan crumble and toasted marshmallows – buttery, creamy, not overly sweet, and perfect for a holiday side dish.

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Ingredients

Casserole Base

• 6 sweet potatoes
• ⅓ cup (75 g) butter
• ½ cup (120 g) sour cream
• 2 large eggs, beaten
• 1 teaspoon vanilla extract
• ½ teaspoon salt
• ¼ teaspoon black pepper

Crunch Topping

• ½ cup (100 g) brown sugar
• ¾ cup (90 g) chopped pecans
• 3 tablespoons (24 g) all-purpose flour
• 3 tablespoons (45 g) melted butter

Finishing

• 2 cups (about 100 g) mini marshmallows

Instructions

1. Peel sweet potatoes and roughly chop into large chunks. Place them into a large pot and cover with salted water. Bring to a boil, then reduce heat to medium-low and simmer until tender, about 20 to 30 minutes. Drain well.
2. Preheat oven to 375°F (190°C).
3. Mash the sweet potatoes with butter, sour cream, salt, and pepper. Beat in eggs and vanilla until smooth. Spread the mixture evenly into a greased 9×13-inch baking dish.
4. Make the topping: In a small bowl, stir together brown sugar, pecans, and flour. Mix in melted butter until crumbly. Sprinkle the topping evenly over the sweet potatoes.
5. Bake uncovered for 30–35 minutes, until hot and the topping is lightly browned.
6. Remove casserole from oven, sprinkle evenly with mini marshmallows, and return to oven for 8–10 minutes, until marshmallows are puffed and golden.

Recommended Products

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• 
  Pyrex Basics 3 QT Glass Baking Dish With Plastic Lid
• 
  Pyrex Deep Baking Dish Set
• 
  Casserole Dish

Nutrition Information:

Yield:

10

Serving Size:

1 cup
Amount Per Serving: Calories: 256Total Fat: 6gSaturated Fat: 3gTrans Fat: 0gUnsaturated Fat: 2gCholesterol: 48mgSodium: 174mgCarbohydrates: 44gFiber: 3gSugar: 6gProtein: 7g

This information is provided as a courtesy and for entertainment purposes only. This information comes from online calculators. Although frugalmomeh.com attempts to provide accurate nutritional information, these figures are only estimates.

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