Preheat the oven: Preheat your oven to 425°F (220°C). Line a large baking sheet with parchment paper if desired.
Prepare the sweet potatoes: Wash and scrub the sweet potatoes thoroughly. Peel them if preferred, then cut them into evenly sized fries about ¼ to ½ inch thick.
Soak the fries: Place the cut sweet potatoes in a large bowl of cold water and soak for about 30 minutes.
Dry thoroughly: Drain the sweet potatoes and pat them very dry with clean kitchen towels or paper towels. Removing excess moisture is important for better browning.
Add cornstarch: Place the dried fries in a large bowl and sprinkle with cornstarch. Toss gently until they are lightly coated.
Season: Add the olive oil, paprika, garlic powder, salt, and black pepper. Toss until the fries are evenly coated.
Arrange on the baking sheet: Spread the fries in a single layer on the prepared baking sheet. Leave space between the fries and avoid overcrowding the pan.
Bake: Bake for 15 minutes, then carefully flip the fries.
Finish baking: Return the baking sheet to the oven and bake for another 10–15 minutes, or until the fries are tender and the edges are golden brown.
Serve: Remove from the oven and let the fries cool for a few minutes. Serve warm with your favorite dipping sauce.