Preheat oven to 425 degrees F. Spray or brush a baking sheet or aluminum foil with oil.
Using a sharp knife, cut slits into each potato, being careful not to slice all the way through.

I used two wooden spatulas on either side of the potato to help stop the knife from slicing all the way through.

Make seasoning with olive oil, melted butter, salt and pepper and cheese with parsley in a bowl.

Spread the seasoning over the potato with a brush coating each slice nicely.
Arrange the potatoes on the baking sheet.
Brush the melted butter over each potato and the sprinkle some more salt, pepper, and garlic powder.

Make sure to get in between the slices of the potatoes with the butter and seasonings.

Bake for 20 minutes. Remove to sprinkle with parmesan cheese.

Return to the oven to bake for an additional 20-25 minutes, or until they are crispy on the outside and fork-tender on the inside.

Remove from the oven, sprinkle with more parmesan cheese and freshly chopped parsley.

Serve hot.