Preheat the oven to 450°F. Line a large rimmed baking sheet with parchment paper.
Scrub the sweet potatoes, then pat them dry with paper towels or a clean kitchen towel.
Cut the potatoes into long, thin (½-inch-thick) sticks. To do this, first slice off the ends. Then, cut the potatoes in half lengthwise. Place one potato half in front of you, cut-side down. Cut it in half, lengthwise, then cut both quarters into long, ½-inch-thick slices. Finally, flop the sliced potato quarter onto its other cut side and cut it lengthwise into ½-inch-thick sticks. (See the video for a step-by-step demo.)
Spread out the sweet potato sticks on the prepared baking sheet. Drizzle with olive oil, season with salt and pepper, and use your hands to mix the sweet potato sticks with the seasonings until they're evenly coated.
Put the baking sheet on the middle rack of the oven. Roast for 20 to 25 minutes, until the sweet potato fries are tender in the middle and beginning to brown on the outside.
Remove the baking sheet from the oven. Serve the sweet potato oven fries with ketchup, mayo, honey mustard dressing, or your favorite dipping sauce.