In 12-inch skillet, heat oil over medium heat until bubbly. Pour egg mixture into skillet. As mixture begins to set at bottom and side, sprinkle with 1/2 cup of the cheese and all of the pepperoni. Gently lift cooked portions of egg with spatula so that thin, uncooked portion can flow to bottom and turn over gently to cook evenly (avoid constant stirring). Cook until eggs are thickened throughout but still moist.