Preheat oven to 450 degrees F.
In a large bowl, toss the potatoes with the melted butter, olive oil, seasoned salt, cayenne, parsley, and 3 tablespoons of the Parmesan.
Arrange in a single layer on 2 sheet trays. Bake until golden brown and crisp, about 45 minutes. Turn the potatoes halfway through the cooking with flat spatula.
Remove from oven and taste for seasoning. Add some kosher salt to taste and transfer to a serving platter. Garnish with more Parmesan and serve.