Mexican Coke is the original coke formula, made with sugar cane and not corn syrup. there for older people tend to worship this as it is what they grew up drinking.
The story of how Mexican Coke was coined,

Coke: were going to switch to corn syrup

Mexico: yo, fuck that holmes
by dabgnorts April 15, 2009
After having anal sex, you piss brown shit into a bottle.
I gave a mexican coke to my friend and he drank it.
by Johnnie Quartz January 3, 2008