A protein and a complex carb!! Like chicken and brown rice. Lots of long term energy. Also my advice is just sneak food. The new rule is that it's safe to eat though some hospitals might be slow to catch on. Just make sure someone knows you ate in case of a very very rare emergency :)
Anything lol cuz you won't be eating at all until your baby comes out, they say if you go passed like 24 hours they will let you eat something but only if you don't have the epidural lol I got induced so i couldn't eat passed midnight lol and I had a 16 hour labor, I didn't eat for over 24 hours, and it sucks lol