Preheat your oven to 400°F (200°C). Line a large baking sheet with parchment paper or lightly grease it with oil to prevent sticking and promote even browning.

Wash the baby potatoes thoroughly and slice them in half. Place the halved potatoes in a large mixing bowl.

In a small bowl, stir together the melted butter, minced garlic, grated Parmesan, dried rosemary, onion powder, salt, and pepper. The mixture should be aromatic, thick, and slightly gritty from the cheese.

Pour the garlic butter mixture over the halved potatoes. Use clean hands or a spatula to toss until every piece is evenly coated—make sure the Parmesan mixture clings to the surface of the cut potatoes.

Spread the coated potatoes cut side down in a single layer on your prepared baking sheet. Roast in the preheated oven for 25–30 minutes. About halfway through (around the 15-minute mark), flip them gently to ensure even browning.

The potatoes should be fork-tender, golden brown, and crispy around the edges. You’ll notice the cheese caramelized slightly—don’t worry, that’s the best part!

Transfer to a serving platter and garnish with chopped fresh parsley if desired. Serve immediately while hot and crisp.