Sweet Potato Casserole with Pecan Streusel for Thanksgiving

Sweet Potato Casserole with Pecan Streusel is a classic Thanksgiving dish that's both sweet and crunchy. The smooth, creamy sweet potatoes get topped with a crunchy pecan streusel that adds…

By Ashley • October 5, 2025 • Reading time: 6 min

Save to Pinterest Print

Tip: save now, make later.

Sweet Potato Casserole with Pecan Streusel is a classic Thanksgiving dish that’s both sweet and crunchy. The smooth, creamy sweet potatoes get topped with a crunchy pecan streusel that adds just the right amount of texture and nuttiness. It’s a comforting side that feels like a little celebration in every bite.

I love making this casserole because it’s such a crowd-pleaser and feels like the ultimate holiday treat. The pecan streusel on top brings a lovely mix of buttery, sweet, and crunchy flavors that keep everyone coming back for more. Plus, it’s surprisingly easy to put together, which makes it perfect when you have a busy kitchen on Thanksgiving day.

My favorite way to serve it is fresh out of the oven while the topping is still warm and crisp. It pairs perfectly with turkey and all the other Thanksgiving fixings. I always look forward to this dish because it feels like the sweet ending to a day full of good food and even better company.

Key Ingredients & Substitutions

Sweet Potatoes: The star here—aim for fresh, firm sweet potatoes for creamy mash. If you’re short on time, canned mashed sweet potatoes work too, just drain well to avoid excess moisture.

Butter: Unsalted butter gives control over saltiness. You can swap for margarine or coconut oil for a dairy-free version, but note the flavor will be slightly different.

Pecans: They add crunch and flavor to the streusel. If you don’t like pecans, walnuts or almonds make excellent alternatives.

Milk: Whole milk gives richness, but you can use 2%, almond, or oat milk to keep it lighter or dairy-free.

Sugar & Brown Sugar: Granulated sugar sweetens the potatoes while brown sugar adds caramel notes to the streusel. Maple syrup or honey can substitute in the sweet potato base for a natural twist.

How Do You Get a Perfectly Crispy Pecan Streusel Topping?

The streusel topping is all about the right texture—crumbly and crisp, not soggy. Here’s how to nail it:

• Mix your dry ingredients with melted butter just until combined; don’t overmix to keep crumbs intact.
• Sprinkle the topping evenly over the sweet potatoes to get uniform crispness.
• Bake at 350°F (175°C) for 30-35 minutes—long enough for the topping to turn golden but watch closely to avoid burning.
• Let the casserole rest a few minutes after baking; it helps the streusel harden slightly for that perfect crunch.

Equipment You’ll Need

• Large mixing bowl – perfect for mashing sweet potatoes and mixing all the ingredients smoothly.
• Potato masher or fork – makes mashing cooked sweet potatoes quick and easy without lumps.
• 9×13 inch baking dish – roomy enough to hold the casserole and allows the topping to crisp evenly.
• Measuring cups and spoons – help you get the right amounts of sugars, spices, and butter every time.
• Spatula or wooden spoon – great for stirring the streusel topping and spreading the sweet potato layer evenly.

Flavor Variations & Add-Ins

• Add a pinch of ground nutmeg or allspice to the sweet potato base for a warm, autumnal spice flavor.
• Swap pecans for chopped walnuts or almonds to change up the nutty crunch with different textures.
• Mix mini marshmallows on top instead of pecan streusel for a classic sweet, gooey twist.
• Stir in some orange zest or a splash of fresh orange juice into the sweet potato mixture for a bright, citrusy note.

Sweet Potato Casserole with Pecan Streusel for Thanksgiving

Ingredients You’ll Need:

For the Sweet Potato Base:

• 4 cups mashed sweet potatoes (about 3-4 medium sweet potatoes)
• 1/2 cup granulated sugar
• 2 large eggs
• 1/3 cup unsalted butter, melted
• 1/2 cup milk (whole or 2%)
• 1 teaspoon vanilla extract
• 1/2 teaspoon ground cinnamon
• 1/4 teaspoon salt

For the Pecan Streusel Topping:

• 1 cup chopped pecans
• 1/2 cup all-purpose flour
• 1/2 cup light brown sugar, packed
• 1/4 cup unsalted butter, melted
• 1 teaspoon ground cinnamon
• Pinch of salt

Time Needed

This sweet potato casserole takes about 15 minutes to prep, plus 20 minutes boiling or up to an hour baking the sweet potatoes. Once assembled, bake the casserole for 30-35 minutes until the topping is golden and crispy. Overall, expect around 1 hour and 15 minutes to 1 hour and 45 minutes total, depending on how you cook your sweet potatoes.

Step-by-Step Instructions:

1. Prepare Your Oven and Dish:

Start by preheating your oven to 350°F (175°C). Lightly grease a 9×13 inch baking dish or similar with butter or cooking spray to keep the casserole from sticking.

2. Cook and Mash the Sweet Potatoes:

Wash and peel your sweet potatoes. You can boil them in water for about 20 minutes or bake them whole for 45-60 minutes until they are tender and easily mashed. Once cooked, mash them in a large bowl until smooth.

3. Make the Sweet Potato Mixture:

To the mashed sweet potatoes, add granulated sugar, eggs, melted butter, milk, vanilla extract, cinnamon, and salt. Mix everything together thoroughly until you have a smooth, creamy mixture.

4. Prepare the Pecan Streusel Topping:

In a medium bowl, combine chopped pecans, flour, packed brown sugar, melted butter, cinnamon, and a pinch of salt. Stir gently until the mixture forms crumbly clusters and the pecans are evenly coated.

5. Assemble and Bake:

Spread the sweet potato mixture evenly into the greased baking dish. Sprinkle the pecan streusel topping evenly over the surface. Place the dish in the oven and bake for 30-35 minutes, or until the topping turns golden brown and the casserole is heated through and bubbly around the edges.

6. Serve and Enjoy:

Remove the casserole from the oven. Let it cool for about 5-10 minutes before serving so the topping can set and the casserole is warm, but not too hot. Serve as a delicious, comforting side dish, perfect for Thanksgiving or any festive meal.

Can I Use Frozen Sweet Potatoes for This Casserole?

Yes, you can use frozen mashed sweet potatoes to save time. Just make sure to thaw them completely and drain any excess liquid before mixing to avoid a watery casserole.

Can I Make the Casserole Ahead of Time?

Absolutely! Prepare the sweet potato base and streusel topping separately, then assemble just before baking. You can refrigerate the assembled casserole for up to 24 hours before baking. Add a few extra minutes to the baking time if baking straight from the fridge.

How Should I Store Leftovers?

Store leftovers in an airtight container in the refrigerator for up to 3 days. To reheat, warm in a 350°F oven until heated through and the topping is crisp again, or microwave individual portions.

Can I Substitute the Pecans in the Streusel Topping?

Yes! Walnuts or almonds work great as a substitute if you prefer or have a nut allergy. Just chop them roughly and use the same amount as the pecans called for in the recipe.