Warm the oven to 390°F and line two sizable baking trays with parchment paper.
Separate each potato into eight wedges of uniform dimension. Halves the longitudinally. Again, cut in half along the length. Finally, fold the sections in half along their length.
In a large Ziploc bag, combine the oil, garlic powder, garlic salt, and pepper. Toss in the potato wedges until they are coated evenly.
Distribute the segments in a uniform and single layer across both baking sheets. Ensure that the skin-facing side of the pan is facing downward.
Add an additional pinch of salt and half of the Parmesan cheese, if desired.
While baking, rotate the segments halfway through the thirty minutes. Toast until golden, crisp, and a probe test indicates that the food is done.
Warmly garnish with the remaining Parmesan cheese and parsley.