Preheat the Oven: Preheat your oven to 425°F (220°C). Place a baking sheet inside the oven while it heats to get it nice and hot.
Prepare the Sweet Potatoes: Peel the sweet potatoes (optional) and cut them into ¼ inch thick fries. Try to make them as uniform as possible to ensure they cook evenly.
Soak the Fries: Place the cut sweet potato fries in a bowl of cold water for 30 minutes. This step removes excess starch, which is key to getting crispy fries.
Season the Fries: After soaking, drain and pat the fries dry with a paper towel to remove moisture. In a large bowl, toss the fries with 2 tablespoons olive oil, 1 teaspoon garlic powder, 1 teaspoon paprika, 1 teaspoon salt, and ½ teaspoon black pepper. If you're using cornstarch for extra crispiness, sprinkle it in now and toss everything together.
Bake the Fries: Carefully remove the hot baking sheet from the oven. Spread the fries in a single layer on the sheet, ensuring they aren’t overcrowded. Bake for 25-30 minutes, flipping the fries halfway through, until they are golden brown and crispy.
Check for Crispiness: Once the fries are crisp and golden, remove them from the oven and let them cool for a few minutes before serving.