In a medium bowl, whisk together the whole eggs, liquid egg whites, sea salt, black pepper, and garlic powder until the mixture is light and frothy.
Place a large non-stick skillet over medium-low heat and add the ghee, swirling to coat the pan as it melts.
Add the baby spinach to the skillet and sauté for 1-2 minutes until the leaves are just wilted.
Pour the egg mixture into the skillet over the spinach and let it sit undisturbed for about 30 seconds to begin setting.
Using a silicone spatula, gently push the eggs from the outer edges toward the center, creating soft, creamy curds.
When the eggs are about 80% cooked and still appear slightly moist, sprinkle the crumbled feta cheese evenly over the top.
Continue to gently fold the eggs for another 30-60 seconds until the cheese is warm and the eggs are fully set but still tender.
Remove from heat immediately and serve on a warm plate to maintain the velvety texture.