1. In a large bowl, whisk the 18 eggs together.
2. In a medium pan, saute the onion in the olive oil until tender. Add the garlic. Cook for 2-3 minutes.
3. Add the onions and garlic to the eggs. Stir in the sun dried tomatoes and artichokes. Add the parsley and salt and pepper. Stir in the feta cheese.
4. Pour the egg mixture into a 9 by 13 glass Pyrex dish that has been coated with cooking spray. If you want, you can add extra cheese to the top of the egg mixture once it is in the pan.
5. Bake in the oven at 350 degrees for 40-45 minutes.
6. Let the egg casserole cool in the pan for about 10 minutes before cutting. Cut into squares and serve.