Greek Potato Skins with Olives and Feta

Prep time: 5 minutes Cook time: 45 minutes Serves 4 Ingredients: 2 russet potatoes or Maris Piper potatoes 3 tablespoons olive oil, divided, plus more for drizzling (optional) 1 teaspoon rock salt, divided ¼ teaspoon black pepper 2 tablespoons fresh coriander, chopped, plus more for serving 60 g Kalamata olives, diced