First, preheat your oven to 425°F (220°C). This will ensure even roasting. While the oven warms, wash your fingerling potatoes thoroughly to remove any dirt.

Banishing dirt is crucial; who wants to bite into grit? Slice them lengthwise, exposing the interior that will absorb your seasonings.

In a large bowl, toss those sliced potatoes with olive oil, lemon juice, garlic powder, smoked paprika, oregano, sea salt, and freshly ground black pepper. Make sure they're evenly coated. Nothing’s worse than a dry potato slice!

Spread the seasoned potatoes cut-side down on a lined baking sheet. This position guarantees they get crispy. Leaving enough space is key; a crowded sheet could lead to steaming, which doesn’t do anyone any good when you're aiming for crispy.

Slide the baking sheet into your preheated oven. Let the potatoes roast for about 25-30 minutes. Halfway through, flip them, allowing both sides to embrace that crispy texture. You want them golden brown.

Once they’ve reached that perfect level of roasted goodness, remove them from the oven. While they’re hot, toss with butter and a sprinkle of Parmesan. This should melt over the potatoes beautifully.

Serve the roasted fingerlings warm, topped with coarse sea salt, cracked black pepper, and fresh parsley. Presentation matters! The pop of green from the parsley makes the dish visually appealing.