Preheat your oven to 425°F (220°C).
Wash the sweet potatoes and peel if desired. Cut them into uniform fry shapes, about 1/4 inch thick.
In a mixing bowl, combine the sweet potatoes with olive oil, cornstarch, kosher salt, and black pepper. Toss until evenly coated.
Line a baking sheet with parchment paper and spread the fries in a single layer.
Bake for 20-25 minutes, flipping halfway through.
Check for doneness; fries should be golden brown and crispy. Bake longer if necessary.
Let cool for a few minutes and serve with your favorite dipping sauce.