Preheat oven to 375 degrees Fahrenheit.
Insert chopstick into the bottom of the potato, going all the way through lengthwise. Starting from the top, cut a spiral, using the chopstick as a guide, all the way down to the bottom. Gently spread apart the layers of the spiral, then carefully remove from the chopstick. Repeat with remaining potatoes.
Place potatoes on a baking sheet lined with parchment paper.
Brush the melted butter all over potatoes. Season evenly with salt and pepper.
In a bowl, mix together Parmesan cheese, garlic powder, onion powder, paprika and parsley.
Sprinkle Parmesan mixture over potatoes, making sure to get in between each layer.
Bake in oven for 45 minutes, until potatoes are cooked through and crispy on the outside.