Preheat oven to 425°F. Toss potatoes with 3 tablespoons oil, 2 tablespoons lemon juice, ½ teaspoon dried oregano, ½ teaspoon each onion powder and salt and ¼ teaspoon pepper on a large rimmed baking sheet until well coated.
Roast, tossing once, until golden brown and crispy, 20 to 25 minutes. Transfer to a platter. Garnish with lemon zest, lemon juice and/or chopped oregano, if desired.
