Preheat oven to 450°F. Generously coat two rimmed baking sheets with vegetable cooking spray or olive oil. Toss the potatoes with oil and season with salt and pepper.
Divide potatoes between the baking sheets, arrange in a single layer, without overlapping. Bake the potato fries, until browned and tender, tossing once for about 25 to 30 minutes. Sprinkle with lemon juice; season with salt and pepper, if desired. Toss to coat.