Preheat the oven to 395 F | 200 C.
In a large bowl, toss potatoes, lemon juice, oil, salt, pepper, oregano, garlic and cayenne pepper. Place in a large baking dish.
Roast in the middle of the oven for about 30 minutes. Remove from the oven, add melted butter and toss the potatoes carefully with a spoon then bring back in the oven.
Increase the temperature to 425 F | 220 C and roast until the liquid is dried. About 25 minutes.
Remove, sprinkle with parsley and serve immediately.
