Representative of the American south here! Current slang is as follows

Hispanic - Taco
Asian - We usually just say Asian but when we don't, I typically hear "Rice-eye"
Middle-eastern - Haji, towelhead, One of my friends says "Sand Niggers" but I havent heard anyone else use it
Black - Again, I usually hear black, with the classic "Nig" used when it isn't
Europeans - Cheese-heads, Brits for the British, and "Kings of Surrender" for the French.

Note most languages have their own descriptors as well, with Spanish and its offshoots called the "Taco Languages" and Asian languages being "Moonspeak" for example

Disclaimer: I am not racist, please don't misconstrue this as such