If you're cooking in the middle of the night just because you woke up hungry, just have a snack or sandwich, glass of water or milk. That being said, it's generally not healthy to eat in the middle of the night because you probably aren't going to do anything with those calories, and digesting can keep you from falling back asleep, especially if you get too full. Plus doing an activity that requires movement and focus will not help you get back to sleep if you need to. Unless you have to stay awake to do something during night, then I would try to avoid it. Maybe keep some water and crackers near your bed?