Creamy, spiced sweet potatoes topped with a crunchy, buttery pecan streusel. This iconic side dish is the ultimate balance of sweet, savory, and texture for your holiday table.
No holiday table is complete without this beloved Sweet Potato Casserole. It beautifully bridges the line between side dish and dessert. The base is luxuriously smooth and creamy, made from roasted or boiled sweet potatoes enriched with butter, cream, and warm spices.
The crowning glory is a crunchy, buttery pecan streusel that bakes into a irresistible caramelized topping. Every bite offers the perfect contrast of soft, sweet potatoes and crisp, nutty crumble. It’s a make-ahead dream and always a crowd favorite.
The Science of the Creamy Base & Crisp Topping
The perfection of this casserole lies in managing two distinct textures. The creamy sweet potato base gets its smooth, spreadable consistency from the natural starches in the potatoes, which gelatinize when cooked and mashed.
Adding fat (butter, cream) and eggs coats the starch molecules and adds richness, while the eggs also help the mixture set as it bakes, preventing it from being runny. The pecan streusel topping achieves its crunch through the Maillard reaction and the careful ratio of fat to dry ingredients.
Brown sugar caramelizes, butter solids brown, and the nuts toast, all contributing deep flavor. The flour provides structure, creating distinct crumbles that stay crisp rather than melting into the soft filling below, thanks to the insulating layer formed during baking.
Ingredients
For the Sweet Potato Filling:
- 3 lbs (about 4-5 medium) sweet potatoes, peeled and cubed
- ½ cup (1 stick / 113g) unsalted butter, melted
- ⅓ cup (80ml) heavy cream or whole milk
- ½ cup (110g) packed light brown sugar
- 2 large eggs, lightly beaten
- 1 teaspoon vanilla extract
- 1 teaspoon ground cinnamon
- ½ teaspoon ground nutmeg
- ¼ teaspoon salt
For the Pecan Streusel Topping:
- 1 cup (110g) chopped pecans
- ½ cup (65g) all-purpose flour
- ½ cup (110g) packed light brown sugar
- ¼ cup (½ stick / 57g) unsalted butter, cold and cubed
- ¼ teaspoon salt
Instructions
1. The Cooked & Mashed Sweet Potatoes: Cook the peeled, cubed sweet potatoes in boiling water until very tender, about 15 minutes. Drain well and return to the pot. Mash until completely smooth with no lumps.
2. The Combined Filling Ingredients: To the mashed sweet potatoes, add the melted butter, cream, brown sugar, beaten eggs, vanilla, cinnamon, nutmeg, and salt. Stir vigorously until the mixture is very smooth, creamy, and uniformly combined.
3. The Spread Filling in the Dish: Transfer the sweet potato mixture to a greased 9×13 inch baking dish. Use a spatula to spread it into a perfectly smooth, even layer.
4. The Mixed Streusel Topping: In a medium bowl, combine the chopped pecans, flour, brown sugar, and salt. Add the cold, cubed butter. Using your fingers or a pastry cutter, work the butter into the dry ingredients until the mixture resembles coarse crumbs with some pea-sized pieces.
5. The Topped Casserole Before Baking: Sprinkle the streusel topping evenly over the entire surface of the sweet potato filling, covering it completely.
6. The Baked, Golden-Brown Casserole: Bake at 350°F (175°C) for 30-35 minutes, until the filling is set (it should not jiggle when shaken) and the streusel topping is deep golden brown and crisp.
7. The Slightly Cooled Casserole: Let the casserole cool on a wire rack for 15-20 minutes before serving. This allows the filling to set further for cleaner slices.
8. The Scooped Serving: Use a large spoon to scoop out portions, making sure to get both the creamy filling and the crunchy topping in each serving.
9. The Plated Side Dish: Transfer a generous scoop to a serving plate or bowl. It’s now ready to be enjoyed as the star side dish of your holiday meal.
Pro-Tips for Casserole Perfection
- Choose the Right Potatoes: Jewel or Garnet sweet potatoes (with orange flesh) are sweeter and have a smoother texture than white-fleshed varieties.
- Get a Smooth Puree: For an ultra-silky texture, pass the mashed potatoes through a ricer or food mill, or even blend with an immersion blender.
- Balance the Sweetness: Taste your filling before baking. Sweet potato sweetness varies. Adjust brown sugar to your preference.
- Cold Butter for Streusel: Using cold butter is crucial for achieving a crumbly, crisp topping rather than a greasy, melted one.
- Make Ahead: Assemble the entire casserole (through step 5), cover, and refrigerate for up to 24 hours. Let sit at room temp for 30 minutes before baking. You may need to add 5-10 minutes to the bake time.
- Marshmallow Option: For a traditional marshmallow top, omit the streusel. Bake the filling for 20 minutes, then top with 2-3 cups of mini marshmallows and bake 5-10 more minutes until golden and puffed.
- Storage & Reheating: Store leftovers covered in the fridge for up to 4 days. Reheat in the oven at 350°F for best texture (microwave will soften the topping).
- Nut-Free Variation: Replace pecans with old-fashioned rolled oats for a similar crunchy texture.
- Serving: This is rich! A little goes a long way. It pairs beautifully with savory main dishes like roast turkey or ham.
This Classic Sweet Potato Casserole is a guaranteed highlight of any festive gathering.
