Preheat the oven to 300F/150C. Line a large baking sheet with baking paper. Separate the eggs, placing the yolks in a small bowl and the whites in the bowl of a stand mixer with the whisk attachment. Add the cream of tartar to the egg whites and beat on high speed for 5-8 minutes until meringue peaks form. Use a spatula to transfer to a separate bowl.
Add the cream cheese to the same stand mixer bowl and beat on high to soften. As it’s beating, drop in the egg yolks one at a time to combine, ensuring completely smooth. Add the Italian seasoning, onion powder and sea salt and combine.
Use a silicone spatula to gently fold the meringue into the herby yolk mixture. Folding the mixture in a clockwise motion will help retain the firm texture while adding to the air. Avoid stirring as this will deflate the meringue.
Pour the mixture onto the lined baking tray. Spread into a rectangle shape about ¾-inch thick. Use the spatula or the back of a spoon to ensure an even layer for even baking. Sprinkle with rosemary (optional). Bake in the middle of the oven for 20-22 minutes or until golden on top. Remember to bake low and slow otherwise, it will likely burn before the center is cooked.
Remove from the oven. Leave to cool in the tray for 10 minutes. Drizzle with good quality extra virgin olive oil and a sprinkle of crystal salt before serving.