Burrito bombing is when one goes to Taco Bell and buys a burrito. Then and only then the burrito is completely opened exposing its contents. The burrito is then taken to a place where there is a large gathering of people whereupon the burrito is thrown into the crowd. You and your friends then quickly drive away.
Dude 1: So many middle school nerds gather outside the theater on Friday nights. We should do a drive by burrito bombing!