Prick each potato several times with a fork, wrap in aluminum foil, and bake them for 1¼ hours at 375 degrees. After they’ve cooled, cut each potato in half and scoop out the pulp into a large mixing bowl.
Lower the oven temperature to 350 degrees.
Add sugar, eggs, salt, seasonings, butter, milk and vanilla to the sweet potato pulp. Mix together with a hand mixer until smooth.
Transfer the potato mixture into a baking dish.
Tip: I make two separate casseroles - one to eat immediately and one to freeze for a later meal. Do not add the topping to the dish you’re going to freeze. Add the topping right before baking.
In a medium bowl, mix the brown sugar and flour. Cut in the cold butter until the mixture looks like pea-sized crumbles. Stir in the pecans. Sprinkle the mixture over the sweet potato mixture.
Tip: If you are splitting the recipe, only sprinkle half of the topping onto one casserole and save the other half in an airtight container. Put it in the refrigerator until you bake the second casserole.
Bake in the preheated oven for 30 minutes. Serve warm.