Preheat oven to 400°. Line a large, shallow roasting pan with aluminum foil.

In a large bowl, combine olive oil, parsley, salt, garlic powder, and pepper, whisking to combine well. Add potatoes, tossing to coat. Arrange potatoes in an even layer in prepared pan. Bake for 1 hour, or until potatoes are lightly browned and tender, stirring occasionally.