In a large mixing bowl, whisk together the large eggs, liquid egg whites, and room-temperature chicken bone broth until the mixture is completely combined and smooth.
Stir in the finely chopped baby spinach, minced fresh chives, sea salt, black pepper, and garlic powder.
Lightly grease two large ceramic ramekins or one medium heat-proof glass dish with the ghee to ensure easy removal.
For a truly professional, silky texture, pour the egg mixture through a fine-mesh sieve directly into the prepared ramekins to remove any bubbles or solids.
Cover the ramekins tightly with aluminum foil or a heat-safe lid to prevent water droplets from entering the custard.
Place the ramekins into a steamer basket over a pot of simmering water, ensuring the water does not touch the bottom of the dishes.
Steam on low heat for 12 to 15 minutes, or until the custard is set around the edges but still possesses a slight, gentle jiggle in the center.
Carefully remove the ramekins from the steamer and let them rest for 2 minutes before serving warm.