In a deep pan, bring water to a boil and steam the broccoli and cauliflower for about 15-18 minutes, until fork-tender. Once cooked, strain and set aside to cool.

In the same pan, heat olive oil and sauté the diced onions until translucent, then add spinach and garlic, cooking until spinach wilts and garlic is fragrant.

In a mixing bowl, whisk together eggs, Greek yogurt, and milk until smooth. Add shredded chicken, half the cheese, and the cooled vegetable mixture. Season with herbs and spices, then mix well.

Preheat the oven to 375°F (190°C). Lightly grease a 9x13 inch baking dish with olive oil. Pour the mixture into the dish, spreading evenly and topping with reserved cheese and crushed parmesan crisps.

Bake for approximately 35 minutes or until the top is golden brown and bubbling. For an extra crispy finish, broil for an additional 3 minutes, watching closely.

Once out of the oven, let the casserole rest for about 10 minutes before serving. Optionally garnish with fresh parsley.