Bake sweet potatoes in a 350 degree oven for 90 minutes.
In a large mixing bowl, "cream" the sugar, butter, and eggs using a mixer. (I use a hand mixer.)
While still hot, peel potatoes and remove any dark brown spots. Cut into medium chunks.
Add half of the potatoes, both extracts, lemon juice, and salt to the bowl. Mix well until completely combined.
In a small bowl - whisk milk and flour together until all lumps are gone.
To the large bowl, add remaining potatoes, milk mixture, and spices. Mix well for several minutes, until mixture is smooth and evenly colored. Be sure to remove any strings that get caught in mixer.
Preheat oven to 350 degrees.
Grease a deep pie dish with shortening. Roll pie crust onto dish. Then, starting in the center and working outward, gently press down the dough, making sure to smooth out any air bubbles. Trim any excess dough around the top of the dish.
Pour potato mixture into pie crust, making sure that it's evenly spread out.
Bake pie for 90 minutes.
Remove and let cool. Enjoy!