oh that must be colloquial to the region you were in, I thought the word Tinga originated in Mexico due to the dish being created there, I've heard it used in Spain to describe something vulgar but never heard it as slang for dick.

I don't think that's down to south american slang, I assume you were having chicken and said "polla" rather than "pollo", easily done, I've asked for a dick burrito in a mexican restaurant by accident before luckily the waiter found it hilarious.