01 - Set the grill to medium-high heat, targeting approximately 400°F.
02 - Combine the potato pieces, olive oil, rosemary, thyme, parsley, minced garlic, kosher salt, and black pepper in a large mixing bowl. Toss thoroughly to ensure an even coating.
03 - Cut two large pieces of heavy-duty aluminum foil. Evenly divide the potato mixture between the sheets, spreading into a single layer. Fold the foil over the potatoes and crimp the edges firmly, forming tightly sealed packets.
04 - Arrange the foil packets on the grill grates. Cook for 20 to 25 minutes, rotating once halfway through, until potatoes are fork-tender and lightly browned.
05 - Carefully open the foil packets, avoiding hot steam. If desired, sprinkle with grated Parmesan cheese and extra fresh herbs. Serve immediately while hot.