Preheat your oven to medium-high broil (about 400°F | 200°C).

Place the potatoes in a large pot of salted water. Bring to a boil; cover and cook for 30 to 35 minutes or until the potatoes are tender. Drain well.

Lightly grease a large baking sheet with cooking spray.

Arrange the potatoes on the sheet and slightly flatten them using a potato masher.

In a small bowl, mix the melted butter, garlic, and parsley. Drizzle the mixture over each potato.

Sprinkle with salt and pepper and lightly mist with olive oil.

Broil until golden and crispy (about 10-15 minutes).

Remove from the oven, sprinkle with parmesan, and return to the oven until the cheese is melted.

To serve, season with a bit more salt and parsley, and serve immediately.