Preheat oven to 400 degrees.
In a medium mixing bowl combine eggs, scallions, parsley, oregano, ½ cup of cheese, and heavy cream. Whisk together until thoroughly combined. Season with salt and pepper, to taste.
In a well-seasoned 10-inch cast iron skillet (may also use oven-safe non-stick skillet), heat about 1 tablespoon of olive oil over medium heat.
Add egg mixture and cook for about 5 minutes, or until edges start to set.
Sprinkle remaining ¼ cup of cheese on the top of the eggs.
Transfer skillet to the oven and bake for 10-12 minutes, or until frittata is puffed up, edges are browned, and it jiggles just slightly in the center.
Optional- broil on low for about 30-45 seconds to further brown the cheese topping.