Preheat the oven to 400° F (200°C).
Cut the potatoes in half and put them in a bowl (if using normal sized potatoes cut them in small chunks).
Toss with olive oil, garlic, salt, and pepper until evenly coated.
Transfer to a large enough sheet pan and spread out the potatoes in one layer, cut side down.
Roast in the middle of the oven for 50-60 min flipping them twice during cooking until browned and cooked through.
Take them out of the oven and toss with fresh or dried parsley before serving.