Pre-heat the oven to 425°F.
In a large bowl, toss potatoes, garlic, Parmesan cheese, lemon zest, salt and black pepper; gently mix until well combined.
Drizzle with olive oil; toss again until evenly combined.
Heat a cast-iron skillet, over medium-high heat.
Add butter and heat until melted.
Add potatoes; cook and toss until evenly coated with butter; about 2 minutes.
Just before placiing skillet in the oven, shake a little garlic powder and onion powder on top of potatoes.
Move the skillet to the pre-heated oven.
Roast until soft; 15 to 20 minutes; toss halfway through.
Remove from the oven; top with parsley and serve.