1. Preheat the oven to 425.
2. Cut the sweet potatoes in half horizontally. Then stand each half on end. Slice into 3-4 thick slices. Then, cut each slice into a few thick sticks.
3. Toss on a rimmed baking sheet with the grapeseed oil. Sprinkle with kosher salt and pepper. Bake for 15 minutes. Flip the fries. Bake for another 10 minutes.
4. Serve.