Preheat oven to 400°F. Spray a large skillet with cooking spray and set aside.
In a bowl whisk the eggs and salt, then add in the chopped vegetables and chives and ¼ cup of the cheddar cheese and whisk to combine. Pour into prepared skillet and sprinkle remaining ¼ cup cheddar cheese on top.
Bake for 15 minutes, then remove from oven and allow to cool for 5 minutes, then slice and serve.