Preheat oven to 425 F. Bake sweet potatoes on a baking sheet for one hour or until easily pierced through with a fork and skin is easily removed. Leave oven at the same temperature to use later. Let roasted sweet potatoes stand for a few minutes until easy to handle and no longer steaming. When cooled sufficiently, peel off skin and drain excess liquid or pat dry as much as possible.

Put soft, roasted, peeled potatoes in a large bowl and mash with a potato masher or fork. Add all the rest of the ingredients for the dough and mix together until a dough forms. Transfer to refrigerator and let cool for at least 1 hour.

In the meantime, mix together ingredients for "parmesan" bread crumb coating and place aside in a bowl.

If dough is still too sticky or difficult to work with, add more arrowroot powder 1 tablespoon at a time. Take rounded heaping tablespoons of dough, roll into a ball, and flatten into a thick disc. Press both sides into bread crumb mixture and transfer onto a baking sheet lined with parchment paper. If desired, spray oil onto parchment paper. Use a straw to punch two "eyes" into the discs and the tip of a spoon to make a rounded smile. If desired, spray on top with oil as well.
Bake smiles at 425 for 30-40 minutes, until slightly browned. Let cool and serve with your favorite dipping sauces.