Preheat oven to 325*F
Once sweet potatoes are cooked slice in half and scoop flesh out of each potato and put into a medium sized bowl.
Blend with a hand mixer until smooth and creamy.
Add white sugar, eggs, salt, butter, milk and vanilla extract and mix until smooth.
Transfer to a 9x13 inch pan.
In medium bowl, mix the brown sugar and flour. Using a pasty blender or knives or forks, cut in the butter until the mixture is coarse and resembles small peas.
Stir in the chopped pecans.
Sprinkle the pecan mixture over the sweet potatoes.
Bake in the preheated oven 30 minutes, or until the topping is light brown.