Preheat your oven to 375°F.
Heat the extra virgin olive oil in a small oven-safe skillet over medium heat.
Add the fresh spinach and sauté until it is wilted and vibrant, about 2 minutes.
In a small bowl, whisk together the egg whites, sea salt, black pepper, and garlic powder.
Pour the seasoned egg whites into the skillet over the spinach.
Carefully crack the 4 whole eggs on top of the egg white mixture, spacing them out evenly.
Sprinkle the crumbled feta cheese over the eggs and spinach.
Place the skillet in the oven and bake for 10-12 minutes, or until the whites are set and the yolks remain velvety.
Remove from the oven, garnish with chopped fresh parsley, and serve immediately.