When you have a finger-full (usually the index finger) of sour cream and you sneak up on someone and smear it across their upper lip. Similar to the Dirty Sanchez but done with sour cream as in the movie Still Waiting.
While we were having nachos I Sour Cream Sanchez'ed my date. He was so pissed he Pirate'd me to get even!
by Pandora Handcock February 28, 2009