Preheat oven to 425°F and line a baking sheet with parchment paper.
Peel the sweet potatoes with a vegetable peeler. (You can leave the skins on if you'd like, just wash thouroughly before slicing)
Slice the sweet potatoes into 1/4 inch rounds.
Using a sharp paring knife, carefully cut out jack-lantern faces on each sweet potato.
Place the jack-o-lantern sweet potatoes on a parchment lined baking sheet and drizzle with oil.
Use your hands to spread the oil evenly on the tops and bottoms of the sweet potatoes.
Sprinkle with a little salt and roast in the oven for 25-30 minutes, flipping halfway through. I like to roast mine until the outside is charred a bit.