To make the crust, combine brown sugar, flour, nuts and butter in mixing bowl. Set aside.

Preheat oven to 375F. Spray a medium-size casserole dish with nonstick spray.

Combine sweet potatoes, sugar, salt, vanilla, eggs and butter in a large mixing bowl in the order listed. Beat thoroughly with a hand mixer for about 3-4 minutes to increase the fluffiness of the sweet potato mixture. Add a splash of milk if needed and mix.

Pour mixture into the baking dish. Bake for 25 minutes. At this point, dish can be covered and refrigerated for a couple of days.

Sprinkle the surface of the sweet potato mixture evenly with the crust mixture and return to oven for 10 minutes. Allow to set at least 30 minutes before serving.

The brown sugar and pecan crust should be slightly browned and crunchy.