Make in standard muffin cups, the recipe yields 6, but easily doubled to yield 12 for a full size standard muffin pan.
But for this recipe, smaller size eggs, like US small, or US medium, will work better.
If you don’t mind with overflowing, you can push it with US large eggs, but definitely not US extra large.
Next, just divide batter to fill 6 standard size muffin cups, and top each with an egg, and sprinkle with salt, pepper, and parsley.