I finally nailed the Best Sweet Potato Casserole thanks to a surprising pantry staple most cooks overlook.
I call this the Best Sweet Potato Casserole because it balances silky mashed sweet potatoes with a toastier finish kids and grownups both flip for. The first time I made it I almost skipped the marshmallows, but glad I didn’t they add that slightly burnt sweet pop that changes everything.
It’s the sort of Thanksgiving Recipes Side Dishes that looks simple but hides a couple sneaky techniques I only learned after many tries, and yeah I still mess up sometimes, but it always comes out worth it. If you want comfort without being boring give this version a try.
Ingredients
Ingredient Quantities
- 3 pounds sweet potatoes, cooked and mashed, about 4 cups
- 1/2 cup granulated sugar
- 1/2 cup packed light brown sugar
- 1/2 cup unsalted butter, melted
- 2 large eggs
- 1 teaspoon vanilla extract
- 1/2 cup whole milk
- 1/2 teaspoon salt
- 1 teaspoon ground cinnamon
- 1/4 teaspoon ground nutmeg
- 3/4 cup packed light brown sugar for streusel topping
- 1/2 cup all purpose flour for streusel
- 1/2 cup unsalted butter, melted for streusel
- 1 cup chopped pecans
- 1 teaspoon ground cinnamon for streusel
- 1/4 teaspoon salt for streusel
- 2 cups mini marshmallows or 12 ounces large marshmallows, optional
How to Make this
1. Preheat oven to 350°F (175°C). Roast whole sweet potatoes on a rimmed baking sheet for 45 to 60 minutes until tender, or peel and boil 3 pounds sweet potatoes in salted water 15 to 20 minutes until fork tender; drain and mash to about 4 cups.
2. Put the warm mashed sweet potatoes in a large bowl and add 1/2 cup granulated sugar, 1/2 cup packed light brown sugar, 1/2 cup melted unsalted butter, 2 large eggs, 1 teaspoon vanilla extract, 1/2 cup whole milk, 1/2 teaspoon salt, 1 teaspoon ground cinnamon and 1/4 teaspoon ground nutmeg. Mix until smooth but dont overmix, warm potatoes help everything come together and the butter to melt.
3. Grease a 9×13 inch casserole dish or a 2 quart baking dish and spread the sweet potato mixture evenly in the dish, smoothing the top with a spatula.
4. Make the streusel by mixing 3/4 cup packed light brown sugar, 1/2 cup all purpose flour, 1/2 cup melted unsalted butter, 1 cup chopped pecans, 1 teaspoon ground cinnamon and 1/4 teaspoon salt. Use a fork or your fingers to combine into crumbly clumps; if you want chunkier pecans pulse them lightly in a food processor or chop a bit bigger with a knife.
5. Sprinkle the streusel evenly over the sweet potato layer, pressing lightly so it adheres in places but still has crumbly texture.
6. Bake on the center rack for 25 to 30 minutes until the filling is set and the streusel is golden brown on top.
7. If you want marshmallows, scatter 2 cups mini marshmallows or 12 ounces large marshmallows over the top during the last 5 to 10 minutes of baking and return to oven until melted and lightly browned, or broil 1 to 2 minutes watching closely so they dont burn.
8. Remove from oven and let rest about 10 minutes so it firms up a bit before serving. This helps slices hold their shape.
9. Tip: if your mashed potatoes seem watery, cook them a bit longer to evaporate moisture or mash in a little extra cooked potato to reach 4 cups, and taste the filling before baking to adjust sugar or spice if needed.
10. Store leftovers covered in the fridge up to 4 days and reheat in a 325°F oven until warmed through, or heat individual portions in the microwave.
Equipment Needed
1. Oven set to 350°F (175°C) — you’ll need it preheated
2. Rimmed baking sheet (for roasting) or large pot (for boiling) sweet potatoes
3. 9×13 inch casserole dish or a 2 quart baking dish to bake the casserole in
4. Large mixing bowl for the warm mashed potatoes
5. Potato masher or ricer to get smooth mash, don’t overwork it
6. Measuring cups and spoons for sugars, milk, spices etc
7. Spatula and wooden spoon for folding and smoothing the filling
8. Small bowl and a fork or pastry cutter to make the streusel crumbs
9. Chef’s knife and cutting board for chopping pecans, plus oven mitts for handling hot pans
FAQ
Best Sweet Potato Casserole Recipe Substitutions and Variations
- Sweet potatoes: swap with 4 cups canned pumpkin or 4 cups mashed roasted butternut squash. Pumpkin is a bit wetter so cut the milk by 1 to 2 tbsp or drain a little, and expect a slightly different, earthier flavor.
- Granulated sugar (1/2 cup): use 1/2 cup coconut sugar 1 to 1. It browns similarly and gives a caramel note, not quite as sweet but works fine in the casserole.
- Unsalted butter (1/2 cup, mashed and streusel): replace with melted refined coconut oil or neutral vegetable oil 1 to 1. Refined coconut oil keeps the flavor neutral, unrefined will add coconut notes.
- Chopped pecans (1 cup): substitute with chopped walnuts 1 to 1, or for a nut free option use 1 cup toasted pepitas or 1 cup rolled oats mixed into the streusel for similar crunch.
Pro Tips
1) If the mash looks watery, dry it out before you bake. Spread it on a rimmed sheet or cook it briefly in a skillet to evaporate extra moisture so the casserole sets firm. You can use a tablespoon of cornstarch if you must, but try drying first.
2) Toast the pecans and brown the butter for the streusel. Both steps add a caramel, nutty note that really lifts the topping. Let the browned butter cool a bit before you mix so it doesn’t make the streusel too greasy.
3) Brighten the filling with a little acid and salt. A teaspoon of orange zest or a tablespoon of orange juice and an extra pinch of kosher salt will make the sugars and spices pop, so taste and tweak before it goes in the oven.
4) Add marshmallows at the very end and watch them closely. Bake until warm, then broil 20 to 60 seconds or use a kitchen torch for quick browning. If the streusel is getting too dark, tent the dish with foil around the edges so only the marshmallows finish browning.
Best Sweet Potato Casserole Recipe
I finally nailed the Best Sweet Potato Casserole thanks to a surprising pantry staple most cooks overlook.
8
servings
772
kcal
Equipment: 1. Oven set to 350°F (175°C) — you’ll need it preheated
2. Rimmed baking sheet (for roasting) or large pot (for boiling) sweet potatoes
3. 9×13 inch casserole dish or a 2 quart baking dish to bake the casserole in
4. Large mixing bowl for the warm mashed potatoes
5. Potato masher or ricer to get smooth mash, don’t overwork it
6. Measuring cups and spoons for sugars, milk, spices etc
7. Spatula and wooden spoon for folding and smoothing the filling
8. Small bowl and a fork or pastry cutter to make the streusel crumbs
9. Chef’s knife and cutting board for chopping pecans, plus oven mitts for handling hot pans
Ingredients
3 pounds sweet potatoes, cooked and mashed, about 4 cups
1/2 cup granulated sugar
1/2 cup packed light brown sugar
1/2 cup unsalted butter, melted
2 large eggs
1 teaspoon vanilla extract
1/2 cup whole milk
1/2 teaspoon salt
1 teaspoon ground cinnamon
1/4 teaspoon ground nutmeg
3/4 cup packed light brown sugar for streusel topping
1/2 cup all purpose flour for streusel
1/2 cup unsalted butter, melted for streusel
1 cup chopped pecans
1 teaspoon ground cinnamon for streusel
1/4 teaspoon salt for streusel
2 cups mini marshmallows or 12 ounces large marshmallows, optional
Directions
- Preheat oven to 350°F (175°C). Roast whole sweet potatoes on a rimmed baking sheet for 45 to 60 minutes until tender, or peel and boil 3 pounds sweet potatoes in salted water 15 to 20 minutes until fork tender; drain and mash to about 4 cups.
- Put the warm mashed sweet potatoes in a large bowl and add 1/2 cup granulated sugar, 1/2 cup packed light brown sugar, 1/2 cup melted unsalted butter, 2 large eggs, 1 teaspoon vanilla extract, 1/2 cup whole milk, 1/2 teaspoon salt, 1 teaspoon ground cinnamon and 1/4 teaspoon ground nutmeg. Mix until smooth but dont overmix, warm potatoes help everything come together and the butter to melt.
- Grease a 9×13 inch casserole dish or a 2 quart baking dish and spread the sweet potato mixture evenly in the dish, smoothing the top with a spatula.
- Make the streusel by mixing 3/4 cup packed light brown sugar, 1/2 cup all purpose flour, 1/2 cup melted unsalted butter, 1 cup chopped pecans, 1 teaspoon ground cinnamon and 1/4 teaspoon salt. Use a fork or your fingers to combine into crumbly clumps; if you want chunkier pecans pulse them lightly in a food processor or chop a bit bigger with a knife.
- Sprinkle the streusel evenly over the sweet potato layer, pressing lightly so it adheres in places but still has crumbly texture.
- Bake on the center rack for 25 to 30 minutes until the filling is set and the streusel is golden brown on top.
- If you want marshmallows, scatter 2 cups mini marshmallows or 12 ounces large marshmallows over the top during the last 5 to 10 minutes of baking and return to oven until melted and lightly browned, or broil 1 to 2 minutes watching closely so they dont burn.
- Remove from oven and let rest about 10 minutes so it firms up a bit before serving. This helps slices hold their shape.
- Tip: if your mashed potatoes seem watery, cook them a bit longer to evaporate moisture or mash in a little extra cooked potato to reach 4 cups, and taste the filling before baking to adjust sugar or spice if needed.
- Store leftovers covered in the fridge up to 4 days and reheat in a 325°F oven until warmed through, or heat individual portions in the microwave.
Notes
- Below you’ll find my best estimate of this recipe’s nutrition facts. Treat the numbers as a guide rather than a rule—great food should nourish both body and spirit. Figures are approximate, and the website owner assumes no liability for any inaccuracies in this recipe.
Nutrition Facts
- Serving Size: 290g
- Total number of serves: 8
- Calories: 772kcal
- Fat: 33.9g
- Saturated Fat: 15.9g
- Trans Fat: 0.25g
- Polyunsaturated: 3.1g
- Monounsaturated: 7.6g
- Cholesterol: 109mg
- Sodium: 250mg
- Potassium: 657mg
- Carbohydrates: 85.9g
- Fiber: 6.6g
- Sugar: 52.1g
- Protein: 6.6g
- Vitamin A: 24100IU
- Vitamin C: 4.1mg
- Calcium: 88mg
- Iron: 1.6mg
