In a 10 inch cast iron skillet, heat oil over medium heat. Add potatoes, onion, green pepper, and salt and pepper and cook until vegetables are tender, about 20 minutes, stirring occasionally. Meanwhile, preheat oven to 400 degrees.
2
In a medium bowl, beat eggs with water. Stir in tomatoes and parsley. Mix with potato mixture in skillet. Place in oven and bake for 20 minutes or until set. 5 minutes before omelet is finished, sprinkle shredded cheese over the top.