Cook sweet potatoes in the desired manner until soft.
Preheat oven to 375 degrees F. Spray a 2 qt baking dish with nonstick spray (I use coconut oil spray). Set aside.
Combine cooked sweet potatoes, granulated sugar, salt, vanilla, eggs, and melted butter in a large bowl. Beat with an electric mixer for 4-5 minutes until fluffy and smooth.
Pour into the prepared dish. Bake for 25 minutes.
While baking, prepare streusel topping by combining brown sugar, flour, pecans, and melted butter in a small bowl. Mix with a fork and set aside.
Sprinkle the baked sweet potato mixture with streusel and return to oven for about 10-15 minutes until the crumble is lightly browned. Serve immediately or cover with foil and serve within 30 minutes.