Start by bringing a large pot of salted water to a rolling boil over high heat. Carefully add the 5-6 large Idaho or russet potatoes and let them cook for about 10 minutes, just until they are tender but still firm enough to hold their shape. Drain the potatoes in a colander and allow them to cool slightly, which will make handling easier.

In a large mixing bowl, combine 1/2 cup of extra-virgin olive oil with 2 tablespoons of garlic powder, 1 tablespoon of onion powder, the juice and zest of 1 lemon, 1 teaspoon of kosher salt, 1 teaspoon of freshly ground black pepper, and 2 tablespoons of chopped fresh rosemary. Mix well until all ingredients are combined, creating a fragrant marinade that will elevate the flavor of your grilled potatoes.

While the potatoes are cooling, preheat your grill to medium-high heat, around 400°F. To ensure that your potatoes don't stick, lightly oil the grates with a paper towel dipped in vegetable oil. A proper grill temperature is key to achieving that golden-brown exterior on your crispy herb-grilled potatoes.

Once the potatoes have cooled and are easy to handle, gently toss them in the marinade from Step 2. Make sure each potato is evenly coated for maximum flavor. This will not only add taste but also help achieve a delightful crispiness on the grill. Let them sit for a few moments to soak up all those delicious flavors.

Place the marinated potatoes directly onto the preheated grill. Grill for about 7-10 minutes on each side, turning them once to achieve a beautiful golden color. Keep an eye on them, as visual cues such as a crisp exterior and slight char will tell you they are ready to be flipped.

After grilling, remove the potatoes from the grill and place them in a bowl. Toss the still-hot potatoes with the remaining marinade mixed with 2 tablespoons of freshly chopped parsley for added freshness and color. This final touch ensures that your crispy herb-grilled potatoes are bursting with flavor, ready to impress your guests!