Preheat the oven to 400°F (200°C)
Wash and scrub the sweet potatoes
Pat them dry
Pierce each sweet potato several times with a fork
Rub with a little oil if desired
Sprinkle with salt if desired
Place on a baking sheet lined with foil or parchment
Bake for 45 to 60 minutes, depending on size
Turn once halfway through for even cooking
Check for doneness by inserting a fork or knife
Remove from the oven
Let cool for a few minutes before serving
Slice open and add butter, cinnamon, brown sugar, or other toppings if desired