Preheat oven to 425°F (220°C)
Scrub sweet potatoes clean and pat dry
Poke several holes in each sweet potato with a fork
Rub skins lightly with olive oil (optional)
Sprinkle with salt (optional)
Place sweet potatoes on a baking sheet lined with foil or parchment
Bake 35–60 minutes, depending on size, until tender when pierced with a fork
For extra crisp skin, bake 5–10 minutes longer
Remove from oven and let rest 5 minutes
Split and fluff with a fork before serving
Serve as-is or top with butter, cinnamon, brown sugar, maple syrup, or marshmallows (optional)