“You […]” makes pretty much anything an insult.

A positive word implies sarcasm. “You genius”. “You hero”.

A random noun drags out the negative aspect of the noun or implies lack of a brain. “You french fry”. “You paper bag”.

Adding a random adjective just strengthens the statement. “You british bathroom sink”. “You beautiful parking lot”.

Of couse it depends on delivery, and using random words makes some strange insults, but I rarely see “you […]” turn into a positive compliment.