Preheat oven to 350°F.
Pierce whole sweet potatoes with a fork.
Roast sweet potatoes at 400°F for 45–60 minutes until tender.
Cool slightly.
Scoop flesh from sweet potatoes.
Mash sweet potatoes until smooth.
Measure 2 cups mashed sweet potatoes and place in a large bowl.
Add brown sugar to the bowl.
Mix until evenly blended.
Add eggs.
Mix until combined.
Pour in evaporated milk.
Stir until smooth.
Add melted butter, vanilla, cinnamon, nutmeg, and salt.
Whisk or blend filling until silky.
Place pie crust into a 9-inch pie plate.
Pour filling into the crust.
Tap the pie plate gently to release air bubbles.
Bake at 350°F for 50–60 minutes, until the center jiggles slightly.
Remove from oven.
Cool pie on a rack for at least 2 hours.
Slice and serve.