Prep: Preheat the oven to 420°F (220°C). Place a dark-colored baking sheet in the oven to heat up.
Season the potatoes: Toss the cut potatoes in a large bowl with olive oil, garlic powder, paprika, salt and black pepper. Make sure all potatoes are evenly covered.
Add potatoes to baking sheet: Carefully remove the preheated baking sheet from the oven using oven gloves. Spread the potatoes on it in a single layer. Tuck the rosemary sprigs in between the potatoes.
Bake: Bake the potatoes for around 25-30 minutes, or until tender on the inside and crispy on the outside. You can finish under the broiler for 2-3 minutes to really crisp up the top as well.
Garnish: Sprinkle the hot potatoes with feta, lemon zest and mint. Serve immediately.