Preheat the oven to 425°F and place a piece of foil on a baking sheet.
Use a fork to poke holes into the sweet potatoes, set them on the baking sheet, and roast for 80-90minutes, or until puffed up and soft inside when pierced with a fork.
Split open, butter and place back in the oven for 5 minutes if desired
Serve with desired toppings.
