Preheat your oven to 425°F (220°C). Line a baking sheet with parchment paper to prevent sticking.
Wash and scrub the potatoes. Slice them into rounds, about ¼ inch thick.
In a mixing bowl, toss the potato rounds with olive oil, garlic powder, oregano, salt, and black pepper until evenly coated.
Arrange the potato rounds in a single layer on the prepared baking sheet.
Sprinkle the grated Parmesan cheese evenly over the tops of the potato rounds.
Bake in the preheated oven for 25 minutes, or until the potatoes are golden and crispy, flipping halfway through for even cooking.
Remove from the oven and let them cool for a few minutes. Garnish with fresh parsley if desired.
For extra crispiness, consider broiling the potato rounds for the last 2-3 minutes of cooking.
Serve with a dip, such as ranch or marinara sauce, for added flavor.