Pre-heat oven to 450 degrees.
In a large saucepan add potatoes, cover potatoes with enough water to fully submerge and season with salt.
Boil for 20-25 minutes, checking at 20 minutes with a fork.
Drain and let cool for 5 minutes.
Coat a rimmed baking pan with nonstick cooking spray and transfer cooled potatoes to the pan.
Using a potato masher, spatula or fork lightly press each potato to mash flat.
Brush each potato with 3 Tablespoons of herb compound butter (or unsalted butter) and sprinkle with garlic salt and pepper.
Bake for 20-25 minutes or until potatoes are lightly brown and crisp.
In a small bowl combine parmesan cheese and chives.
Brush the potatoes with the remaining butter and sprinkle with the cheese mixture.
Bake for 2-3 minutes more until the cheese has melted.
Top with bacon, rosemary and more chives if desired.
