Feta cheese and walnuts, the mixture of the gods.
After waking for a pee just last night I couldn’t get back to sleep because of neck pain (a fibromyalgia thing). NSAIDS need to be taken with food so there I was eating cornflakes.
Again, an alien concept to me. But that’s me, different metabolisms are different.
A small hunk of cheese and a piece of fruit. Usually a small apple and a bit of aged cheddar, but whatever combination is available will do.
Add craisins and I’m there.
Why dirty a spoon when you can use the piece of chocolate instead? I get those rectangular bars of high cocoa content chocolate, break off a piece and scoop out some peanut butter (the real stuff, not Skippy). Instant gourmet Reeses. No muss, no fuss.
So… why are you here again?
Oh, and for the OP’s question: Cheese and crackers.
I also like cheese and crackers or peanut butter on crackers. Salsa and chips works, too.
I eat one of my 4 main meals around midnight. So, whatever lunch is. As far as waking up and eating, I’m usually so tired and fast asleep. If I wake up I would probably have to use the bathroom and be slightly dehydrated. So, water or maybe something else with electrolytes. Maybe a pickle.
Another vote for the Cheese Party, but specifically for parmesan. It’s why I buy it. Tho props to Alessan for suggesting feta.
j
I don’t snack at midnight, but when I do, anything from a piece of fruit to a pretzel or cracker. Maybe a few dozen pistachios, or some cashews. Or really whatever there is around. I’m never really hungry (even when I fast once a year), but I am always ready to eat.
Pecans. I have two types: roasted and honey roasted. Sweet and salty. Sometimes a handful of each. I do like a chunk of Monterey Jack sometimes too.
PB&J (usually what I have in the house is strawberry, but if I’m in some sort of utopian paradise where it’s available, I choose apricot or peach), and a glass of milk.
Lately I have really liked canned fish… sardines, Kipper Snanks, herring fillets, etc. Love them in hot sauce. Pretty cheap at Wal-Mart.
Pickle juice.
Like other posters, I never wake up and feel the need to eat. I might get a drink of water when I get up to use the bathroom. If I got out of bed and started making and eating snacks, I’d never get back to sleep!
I’m almost always still up at midnight so I may eat just about anything. Leftovers from dinner, a fried egg, pudding, hot dog, or burrito tops the list.
I’ve done that, too!
All of use peanut butter-out-of-the-jar eaters need to band together and form a club or something. 
I have never even once eaten a midnight snack. I’m not hungry in the middle of the night, or when I first wake up for that matter. But you folks carry on…