Preheat oven to 220°C. Bring a large saucepan of water to the boil over high heat. Add potatoes. Cook for 10 minutes or until almost tender. Drain and pat dry with paper towel. Allow potatoes to cool for 10 minutes.
Cut potatoes in half and place in a bowl. Remove leaves from 1 rosemary sprig and finely chop. Add oil and chopped rosemary to potatoes. Toss to coat.
Spread potatoes, in a single layer, in a lightly greased roasting pan. Top with remaining rosemary sprigs. Roast, turning once, for 35 minutes or until golden and tender. Season with sea salt. Serve.
