Preheat oven to 350 degrees
Combine crust ingredients - brown sugar, flour, nuts and butter in mixing bowl then set it aside
Combine sweet potato mixture ingredients - sweet potatoes, sugar, salt, vanilla, eggs and butter in a mixing bowl in the order listed
Mix thoroughly
Pour mixture into buttered baking dish
Sprinkle the surface of the sweet potato mixture evenly with the crust mixture
Bake for 30 minutes
Allow to set at least 30 minutes before serving