Preheat oven to 350°F (180°C).
Wash and dry potatoes, then cut into halves. Transfer to a medium bowl. Add olive oil, salt and rosemary, then toss to evenly coat the potatoes.
Transfer to a roasting pan and roast in the oven for 30-40 minutes, until crisp and golden brown.
Remove from oven and transfer to a serving platter. Serve warm. Enjoy!