Preheat oven to 425 degrees.
In a gallon-size Ziploc bag, place potatoes, olive oil, garlic, garlic powder and seasoned salt. Zip up the bag and shake it vigorously to evenly coat the potatoes.
Place potatoes in a single layer on a foil-lined baking sheet, setting the ziploc bag to the side for later.
Bake for 30 minutes (flipping halfway through).
Remove from oven and return to the ziploc bag (be careful! They are hot!). Add in the parmesan cheese and fresh parsley, close, and shake it again to coat.
Dump the potatoes back on the foil-lined baking sheet, still in a single layer, and bake for an additional 10 minutes until parmesan cheese has melted and starts to turn golden.
Remove from oven and top with additional parmesan cheese, fresh parsley, and garlic salt. Serve warm.