Typically encountered while partaking in a Latin eating establishments, a Tasty Trevino is when a male takes a shit in a soft shell tortilla. He then jerks himself off and bastes the burrito with cum. At this point, most males choose to flourish their burritos by adding garnishes, but nevertheless, this part is optional. Said garnishes may include, but are not limited to: lettuce, tomatoes, cheese, etc. Once that's through, the male pisses into a cup. He then takes the burrito and cup and presents them to someone to eat.
In a sentence: I went through the drive through yesterday at Taco Bell, and when I pulled up to get my food, the fucking dude gave me a tasty trevino!
Harry: I'll take a burrito and some mountain dew!
Sergio: Anything else, sir?
Harry: No thanks.
*Sergio comes back with a tasty trevino*
Sergio: Your burrito, senor.
*Harry takes a bite*
Harry: WHAT THE FUCK IS THIS YOU DUMB WHORE?!