Bake sweet potatoes until tender. To bake, preheat your oven to 400°F (200°C). Scrub the sweet potatoes clean, then pierce a few times with a fork. Place them directly on a sheet pan lined with foil. Bake for 45–60 minutes, depending on size, until they are very tender and easily pierced with a fork. Let them cool slightly.
Once baked, let them cool slightly, then slice them open and scoop out the sweet potato flesh.
Prepare Filling
In a large mixing bowl, combine the mashed sweet potatoes with the eggs, sugar, melted butter, vanilla, and milk or half-and-half. Mix until well blended.
Grease a casserole dish with nonstick cooking spray. Pour the sweet potato mixture into the dish, spreading it evenly.
Make the Pecan Topping
In a separate bowl, mix together the melted butter that's been cooled, flour, brown sugar, and chopped pecans until combined.
Add Topping and Bake
Sprinkle the pecan streusel on top of the casserole.
Bake at 350°F (175°C) for 30 minutes, or until the topping is golden and the casserole is set.
Notes
Tip: We always roast the sweet potatoes in the oven for better flavor and texture. However, you can also boil peeled, cubed sweet potatoes in salted water instead.Boil Sweet Potatoes (Instead of Baking): To boil sweet potatoes, peel and cut them into cubes. Place the sweet potatoes in a large pot and cover with water. Add a pinch of salt and bring the water to a boil. Reduce the heat and simmer for about 15–20 minutes, until tender when pierced with a fork. Drain the water and let the potatoes cool slightly before mashing or using in your recipe.