2. Pour the olive oil into a medium-size glass baking dish and add the salt and pepper. Stir to combine. Press a rosemary sprig or parsley leaf on the cut side of each potato half and place cut side down in the oil.
3. Bake until the potatoes are nicely browned, 40 to 45 minutes. While the potatoes are cooking, using a spatula, gently move them every now and then to keep them from sticking. When they are ready, remove them from the pan, turning them flat side up and carefully leaving the pressed herb in place. Arrange on a platter and serve immediately.
Note: A glass dish works well in this case because you can check for doneness by carefully holding the dish overhead and looking to see if the potatoes are browned. When you do this, be careful not to spill the hot oil. A metal pan will do, too, but testing for doneness will not be as easy.