Wash and scrub the sweet potato, then dry. Carefully cut into ¼-inch slices.
Place the sliced sweet potatoes in a bowl and cover with cold water. Let soak for 30 to 60 minutes.
Preheat oven to 425°F while sweet potato is soaking.
Drain the sweet potato slices and rinse with fresh water. Dry thoroughly in a single layer with lint-free kitchen towels.
Cut parchment paper to fit baking tray. Place empty baking tray in oven.
Place sweet potatoes slices in a dry bowl and mix thoroughly with olive oil.
Combine cornstarch, smoked paprika, onion powder, garlic powder, and sea salt. Toss thoroughly with sweet potatoes.
Carefully take hot baking tray out of oven and place parchment paper on it, then line up sliced sweet potatoes. Do not crowd them.
Bake for 25 minutes. Take tray out of oven and flip the fries over with a spatula. Bake for another 15 minutes or until crispy. Watch carefully to prevent burning.
Take out of oven and let rest for 5 minutes. Transfer to serving platter and sprinkle with black pepper and parsley.
Repeat the baking process for the rest of the sweet potato with fresh parchment paper.
Notes
Make sure your oven is HOT.
Always preheat the baking sheets.
It is preferable to bake one tray at a time. You will get crispier results by baking on the top rack versus the lower or middle rack. Watch carefully for burning!