Preheat oven to 350 F.
Combine the mashed sweet potatoes with the white sugar, soft butter or margarine, beaten eggs, vanilla and milk. Spoon into a 2 quart oven proof baking dish.
Combine the coconut, flour, brown sugar, chopped nuts and melted butter. Sprinkle over the top of the sweet potatoes.
Bake at 350 F for 30 to 35 minutes.