Preheat the oven to 400ºF.
Bring a large pot of water to a boil. Add the potatoes and cook for 5 to 7 minutes. Drain and set the potatoes aside.
In a large mixing bowl, combine the olive oil, garlic, salt, pepper, thyme, and parmesan. Add the potatoes to the bowl and toss evenly to coat.
Arrange the potatoes on a large greased baking sheet in a single layer, cut side down.
Roast the potatoes in the oven for 25 minutes, flipping halfway with a spatula.
Melt the butter in a small glass mixing bowl and stir in the fresh parsley.
Transfer the roasted potatoes to a serving bowl, drizzle the melted butter mixture on top and toss to coat.
Serve warm, garnished with more parmesan cheese and parsley if liked.
