Scrub potato clean. Slice into thin pieces. Stack and slice into thin strips. Add to a medium bowl. Drizzle with olive oil, parsley, sea salt and optional cayenne. Toss by hand to coat well. Transfer to a parchment line baking sheet.
For soft potatoes cook for 10-12 minutes. Crisp potatoes 15-20 minutes. Toss potatoes with a spatula at the 10 minute mark. Check every 5 minutes after to remove any crisp pieces and allowing the rest to continue cooking to desired doneness.
Transfer to a plate and immediately sprinkle with freshly grated Parmesan cheese.