01 - Preheat oven to 425°F. Line a large baking sheet with parchment paper or lightly grease with olive oil.
02 - In a large bowl, toss the potato pieces with olive oil, rosemary, salt, pepper, and garlic if using, ensuring even coating.
03 - Spread potatoes in a single layer on the prepared baking sheet with the cut side down for optimal crispiness.
04 - Roast for 30 to 35 minutes, turning once halfway, until golden brown and crisp on the edges.
05 - Remove from oven, adjust seasoning if necessary, and serve immediately, optionally garnished with extra rosemary.