Idiom
au naturel
formal
1.
without clothes or without make-up (= substances that women put on their faces to improve their appearance).
I thought I'd leave off the lipstick for a couple of days and go au-naturel.
2.
without having been cooked, or cooked in a very simple way with nothing added.
You can stew these berries briefly with a little sugar or you can eat them au naturel.