Sweet Potato Marshmallow Casserole

Category: Traditional Thanksgiving Recipes & Holiday Favorites

This sweet potato casserole is the ultimate comforting side for Thanksgiving or Christmas. Creamy sweet potatoes are blended with brown sugar, cinnamon, and vanilla, then topped with a crisp pecan streusel and toasted marshmallows. Tips include making it ahead, choosing different toppings like coconut or graham crackers, and ensuring perfect doneness. The mix of textures—fluffy inside, crunchy and sweet on top—makes it a crowd-pleaser for any holiday gathering.

Sarah Crisp
Recipe By Sarah Crisp Sarah Crisp
Last updated on Thu, 13 Nov 2025 19:53:46 GMT
A close up of a sweet potato casserole with marshmallows on top. Pin
A close up of a sweet potato casserole with marshmallows on top. | cookrisp.com

This classic Sweet Potato Casserole with marshmallows and pecan streusel is always the sweet, cozy side dish that disappears fast at every Thanksgiving and Christmas gathering. Packed with creamy mashed sweet potatoes, a golden marshmallow layer, and crunchy pecans, this easy casserole comes together in just 30 minutes plus 20 minutes baking time. Whether you are preparing for a holiday or craving comfort food, this simple sweet potato casserole recipe with marshmallows delivers perfect results every time.

I first made this southern sweet potato casserole on a whim one festive holiday when we needed another side. The creamy filling, buttery crumble, and gooey marshmallow topping quickly became the star at dinner. Each year, someone requests this marshmallow sweet potato casserole, and now it is a must make family tradition that adds comforting, nostalgic flavor with every spoonful.

Gather Your Ingredients

  • Sweet potatoes: Choose orange-fleshed varieties like Jewel or Garnet for vibrant color and creamy texture; fresh is best, but canned yams can be swapped in a pinch
  • Brown sugar: Adds deep caramel notes; use packed light brown sugar for easy measuring and rich flavor
  • Pecans: Provides classic crunch and toastiness; always chop and toast first for maximum nutty aroma
  • Large eggs: Bind the filling to set beautifully; bring to room temperature for smoother mixing and better puff in the oven
  • Milk: Offers creaminess to the casserole; whole milk gives richest taste, but non dairy milks like almond work for dairy free
  • Unsalted butter: Adds richness and tender body to both filling and streusel; use melted or softened as directed
  • Vanilla extract: Rounds out sweet notes and adds aroma; choose pure vanilla for best results
  • Cinnamon and nutmeg: Deliver classic warm spice; use fresh ground cinnamon and nutmeg for stronger flavor
  • Salt: Highlights sweetness and balances ingredients; fine kosher salt or table salt works well
  • All purpose flour: Forms the crumbly, tender streusel top; gluten free flour blends adapt it for special diets
  • Mini marshmallows: The signature topping; swap with cut large marshmallows or coconut for nut free or creative touches

How to Make Sweet Potato Casserole

Boil and Mash the Sweet Potatoes for a Creamy Base:
Peel, cube, and rinse 3 pounds of sweet potatoes. Place in a large Dutch oven and cover fully with water. Bring to a boil over high heat, then simmer over medium for about 15 minutes. When fork tender and bright orange, drain right away to prevent sogginess. Mash until smooth using a masher or hand mixer. Let cool slightly so eggs do not scramble in the next step.
Prepare the Streusel and Toast the Pecans:
On a baking sheet, spread 2 cups pecans and toast in a 350 degree F oven for 5 to 8 minutes, tossing once for even color. Watch carefully for golden edges but not bitter. Coarsely chop when cool. In a bowl, use a fork to combine softened unsalted butter, all purpose flour, packed brown sugar, and a spoonful cinnamon until moist crumbs form.
Mix the Sweet Potato Filling:
Into the cooled mashed potatoes, whisk in half cup brown sugar, two lightly beaten large eggs, half cup room temperature milk, one quarter cup melted butter, a teaspoon vanilla, one teaspoon cinnamon, one teaspoon nutmeg, and half teaspoon salt. Gently stir until creamy and aromatic. Taste for seasoning and adjust as needed.
Assemble and Layer for Ultimate Texture:
Lightly butter or spray a nine by thirteen inch casserole dish. Spread sweet potato filling evenly and smooth the top. Sprinkle half the toasted pecans over the surface for added crunch. Distribute the prepared streusel crumb mixture on top and then scatter mini marshmallows in an even layer. Reserve extra marshmallows to add late if you love gooey topping.
Bake Until Bubbling and Golden:
Bake uncovered at 350 degrees F for 18 to 22 minutes. The filling should puff a little and marshmallows toast to light golden brown. Watch closely after 15 minutes to prevent over browning. If they brown too fast, tent loosely with foil until the filling is hot and topping is perfectly melted and oozy.
Cool, Garnish, and Serve Warm:
Allow casserole to rest 10 minutes before serving so it sets up and flavors come together. Top with reserved pecans before serving for extra crunch. Enjoy as a show stopping holiday side, or reheat leftovers for sweet breakfast casserole the next day.
A casserole with marshmallows on top.
A casserole with marshmallows on top. | cookrisp.com

Last Thanksgiving, my youngest nephew insisted on being the marshmallow helper and now claims the job every year. Toasting the pecans is my trusted trick for an extra layer of nutty aroma, making this sweet potato casserole with marshmallows even more irresistible. Truly, each holiday this recipe creates memories as much as it creates a delicious dish.

Smart Swaps and Variations

For a speedy sweet potato casserole with canned yams, simply substitute equal weights of drained canned yams for fresh potatoes. You can easily make it dairy free by using almond or coconut milk, and a gluten free flour blend in the topping for guests with dietary needs. Nut free families can skip pecans or try sunflower seeds for crunch, while a drizzle of maple syrup or coconut flakes adds warmth and creative new flavor notes for classic marshmallow sweet potato casserole fans.

How to Store and Reheat Sweet Potato Casserole

Store leftover sweet potato casserole covered tightly in the refrigerator for up to four days. For longer storage, transfer to an airtight freezer safe dish and freeze for up to three months. Thaw overnight in the fridge, then reheat at 350 degrees F for 15 to 20 minutes, covering loosely with foil to keep marshmallows from overbrowning. Adding extra marshmallows before reheating brings back that gooey top, while individual portions can be kept in ramekins for easy meal prep and serving.

What to Serve with Sweet Potato Casserole

Pair this sweet potato casserole with roast turkey, green bean casserole, stuffing, or glazed ham for the ultimate holiday meal. For a brunch twist, serve alongside Greek yogurt, oatmeal, or a holiday fruit salad for a comforting breakfast casserole vibe. Present in individual ramekins for potlucks or dress it up with candied nuts and maple drizzle for elegant dining occasions, ensuring everyone gets a taste of tradition.

Nutritional Benefits

This sweet potato casserole is packed with vitamin A and beta carotene for eye health, plus fiber for fullness throughout holiday meals. Pecans and eggs contribute heart healthy fats and extra richness, making this comfort food version nourishing as well as indulgent. Naturally vegetarian, it can also be adapted to gluten free or dairy free diets by using the right swaps so all your guests can enjoy it.

Recipe Success Tips

If your casserole filling seems too runny, make sure potatoes are well drained and cooled before adding eggs and milk. To avoid burning marshmallows, tent loosely with foil or use the broiler only for 30 to 45 seconds for a toasty top. For those who prefer a chunkier texture, mash potatoes just halfway and fold in diced cooked sweet potato before baking, ensuring every bite feels homemade and special.

A spoonful of sweet potato casserole with marshmallows on top.
A spoonful of sweet potato casserole with marshmallows on top. | cookrisp.com

This sweet potato casserole with marshmallows brings festive comfort and crowd pleasing tradition to any meal. Give it a try this season and see why it will become your own family's favorite holiday side.

Common Questions About This Recipe

→ Can I use canned yams instead of fresh sweet potatoes?

Yes, canned yams can be substituted for fresh sweet potatoes. Just be sure to drain them well before mashing for the best texture.

→ How can I prepare this dish ahead of time?

Prepare the filling and topping separately and store both in the fridge. Assemble and bake just before serving for a fresh texture.

→ What toppings work besides marshmallows?

Marshmallows are classic, but streusel, pecans, coconut, graham crackers, or even crushed Ritz crackers offer a unique twist and crunch.

→ How do I avoid a runny casserole?

Drain sweet potatoes well and avoid overmixing the filling. Prepare toppings just before baking for best results.

→ What's the best way to toast the marshmallows?

Add marshmallows in the last minutes of baking and watch closely. Cover lightly with foil if they're browning too fast to keep them perfectly golden.

Sweet Potato Marshmallow Casserole

A November classic, this sweet potato dish topped with marshmallows and pecans is a Thanksgiving and Christmas staple. Brown sugar and warm spices blend for a comforting touch. Whether using canned yams or fresh, it's one to keep handy.

Prep Time
30 minutes
Time to Cook
20 minutes
Complete Time
50 minutes
Recipe By Sarah Crisp: Sarah Crisp

Recipe Type: Thanksgiving

Level of Difficulty: Moderate Difficulty

Cuisine Style: American Southern

Makes: 8 Number of Servings (One 9x13-inch casserole)

Dietary Categories: Suitable for Vegetarians

Ingredients You’ll Need

→ Sweet Potato Base

01 3 pounds sweet potatoes, peeled and diced
02 1/2 cup packed brown sugar
03 2 large eggs, lightly beaten
04 1/2 cup whole milk, at room temperature
05 1/4 cup unsalted butter, melted
06 1 teaspoon pure vanilla extract
07 1 teaspoon ground cinnamon
08 1 teaspoon ground nutmeg
09 1/2 teaspoon kosher salt

→ Streusel Topping

10 6 tablespoons unsalted butter, softened
11 1 cup all-purpose flour
12 1 cup packed brown sugar
13 1 tablespoon ground cinnamon

→ Toasted Pecans

14 2 cups pecans, toasted and roughly chopped, divided

→ Additional Toppings

15 2 tablespoons all-purpose flour
16 2 tablespoons brown sugar
17 1/4 cup unsalted butter, melted
18 1 1/2 cups mini marshmallows

How to Make It

Step 01

Preheat oven to 350 degrees Fahrenheit.

Step 02

Butter or spray a 9x13-inch baking dish with non-stick baking spray; set aside.

Step 03

Spread 2 cups pecans on a baking sheet and toast in the preheated oven for 5 to 7 minutes, watching closely to avoid burning. Remove, allow to cool, and roughly chop.

Step 04

Peel, cube, and rinse sweet potatoes. Place in a Dutch oven or large saucepan; cover with cold water and bring to a boil. Simmer for about 15 minutes or until fork-tender.

Step 05

Drain cooked sweet potatoes thoroughly, transfer to a mixing bowl, and mash until smooth. Allow to cool slightly.

Step 06

Combine mashed sweet potatoes with 1/2 cup brown sugar, eggs, milk, 1/4 cup melted butter, vanilla extract, 1 teaspoon cinnamon, nutmeg, and salt. Fold in half of the chopped toasted pecans. Mix until homogeneous.

Step 07

Transfer sweet potato mixture to prepared baking dish and smooth the surface.

Step 08

In a bowl, use a fork to blend 6 tablespoons softened butter, 1 cup all-purpose flour, 1 cup brown sugar, and 1 tablespoon cinnamon until the mixture forms coarse crumbs.

Step 09

In a separate bowl, mix 2 tablespoons flour, 2 tablespoons brown sugar, and 1/4 cup melted butter until combined. Sprinkle both the streusel mixture and remaining toasted pecans evenly over sweet potato base.

Step 10

Bake in preheated oven for 15 minutes. Remove from oven and evenly distribute mini marshmallows on top. Return to oven and bake for an additional 5 to 7 minutes or until marshmallows are golden brown.

Step 11

Allow casserole to cool for a few minutes before serving.

Extra Suggestions

  1. Prepare the streusel and sweet potato filling separately if making in advance. Keep refrigerated, then assemble and bake before serving.
  2. Keep a close watch while toasting pecans and browning marshmallows to prevent burning.
  3. If marshmallows begin to brown too quickly, tent with foil sprayed with baking spray to prevent over-browning.
  4. For optimal doneness, use an instant-read thermometer; the center should reach 165°F.
  5. Streusel topping can be substituted with coconut, graham cracker crumbs, or crushed Ritz crackers for added texture and flavor.

Things You'll Need

  • 9x13-inch baking dish
  • Mixing bowls
  • Dutch oven or large saucepan
  • Baking sheet
  • Fork or potato masher
  • Measuring cups and spoons
  • Instant-read thermometer

Allergen Information

Always read labels for allergens and consult your doctor if unsure.
  • Contains eggs, milk, tree nuts (pecans), and wheat (flour).

Nutritional Breakdown (Per Serving)

This is for general info and isn't a replacement for professional advice.
  • Calories: 430
  • Fat Content: 18 grams
  • Carbohydrates: 40 grams
  • Protein Content: 15 grams