In a bowl combine eggs, milk, parmesan, parsley and salt and pepper. Set aside.
Preheat oven to 180 degrees C.
Heat oil in an oven-safe frypan and fry onions until brown. Add vegetables and cook for two or three minutes. When vegetables are almost cooked, transfer to a baking dish, add egg mixture, allow to cook for two minutes on the stove then bake in the oven for 7 to 10 minutes, until cooked.