01 - Preheat the oven to 430°F and place a large roasting tray inside to heat up while you prepare the potatoes.
02 - Place the peeled and cut potatoes in a large saucepan. Cover with cold water and add 1 tablespoon salt.
03 - Bring to a boil over high heat, then reduce to medium-low heat and simmer for 8 to 10 minutes until the edges begin to soften but the centers remain firm.
04 - Drain the potatoes well in a colander and let them steam dry for 2 minutes. Return them to the pan and shake vigorously to roughen the edges, creating a crispy texture.
05 - Carefully pour the hot oil or fat over the potatoes in the pan, tossing gently to coat evenly on all sides.
06 - Remove the hot roasting tray from the oven and carefully tip the potatoes into it, spreading them out in a single even layer without overcrowding. Add garlic cloves and herb sprigs if using.
07 - Roast for 20 minutes, then remove from oven and turn each potato using a spatula to ensure even browning.
08 - Return to oven and roast for an additional 20 to 25 minutes, turning once more if needed, until deep golden brown and crispy on all sides.
09 - Sprinkle with sea salt flakes and freshly ground black pepper. Transfer to a serving platter and serve immediately while hot and crispy.