In a 10 inch broilerproof or regular skillet heat oil; add potatoes, onion, garlic, 1/4 teaspoon salt, and the pepper. Cover and cook over medium heat for 5 minutes. Turn potato mixture with a spatula. Cover and cook for 5 to 6 minutes more or until potatoes are tender, turning mixture once more.
In a medium mixing bowl beat together eggs, oregano, and 1/4 teaspoon salt. Pour egg mixture over hot potato mixture. Sprinkle with olives. Cook over medium heat. As the mixture sets, run a spatula around the edge of the skillet, lifting egg mixture to allow the uncooked portion to flow underneath. Continue cooking and lifting edges until egg mixture is almost set (surface will be moist).
Place broilerproof skillet under the broiler 4 to 5 inches from the heat. Broil for 1 or 2 minutes until top is set. (If using a regular skillet, remove the skillet from the heat; cover and let stand for 3 to 4 minutes until top is set.) Sprinkle the top with finely shredded provolone or parmesan cheese. Cut into wedges and serve immediately.