How do you think is the best way to deal with a new coworker that is overstepping their boundaries?

I work as a supervisor in a retail store. We got a new supervisor and she is really sick with power. It’s hilarious-we are supervising cashiers at a retail store, not saving lives or doing anything remotely important. This chick will come tell me when it’s time for me to go to lunch, take a break, or how to do my job. It’s really irritating. What do you think is the best way to deal with this aside from a good ol’ bitch slap? Of course I would like to try and deal with this on my own, in a nice way and come out being able to get along with her.