Place 2 racks in the top and bottom ⅓ of oven then preheat to 425 degrees. Place 2 baking sheets, 1 on each rack, in the oven to preheat along with it.
Scrub sweet potatoes under cool water then blot dry using a kitchen towel. Peel potatoes if desired then trim away any blemishes using a paring knife. Cut potatoes in half then into quarters. Cut each quarter into ¼" matchsticks then place them in a large bowl.
Drizzle olive oil over sweet potato fries then toss until completely coated in oil. Sprinkle fries evenly with salt, cornstarch and desired spices then toss until cornstarch is completely dissolved and there’s a thin film coating each fry.
Remove hot baking sheets from oven then coat with cooking spray. Divide sweet potato fries evenly between baking sheets, separating the fries as far apart as possible. Bake for about 30 minutes, flipping the fries every 10 minutes. Remove from oven then serve nice and hot. Enjoy!
Notes
Be sure to adequately space the fries on the baking sheet. This will prevent the fries from steaming near the others, thus making your fries soggy!