01 - Set oven to 400°F (200°C) and allow to fully preheat.
02 - In a large mixing bowl, combine halved potatoes and sliced red onion. Drizzle with olive oil, add minced garlic, dried oregano, dried thyme, sea salt, and freshly ground black pepper. Toss thoroughly to ensure even coating.
03 - Transfer the seasoned mixture to a baking dish or rimmed baking tray. Spread evenly in a single layer for uniform roasting.
04 - Place in oven and bake for 25 to 30 minutes, stirring once halfway through, until potatoes are just tender and beginning to turn golden.
05 - Remove the dish from oven and distribute crumbled feta cheese evenly over the hot potatoes. Return to the oven and bake for an additional 10 to 12 minutes, until feta is softened and beginning to brown at the edges.
06 - If deeper browning is desired, place under a hot broiler for 1 to 2 minutes, monitoring closely.
07 - Remove from oven, finish with lemon zest and chopped parsley if using, and serve immediately while hot.