with authority 

An exclamation used in basketball to describe a particularly forceful or thunderous slam dunk.

Blake Griffin throws it down with authority, sending the crowd into a frenzy.

with authority by cooberp March 19, 2012

with authoritah 

adv. with gusto, like it was my job. Comes from "with authority," but with authority spelled like Cartman says it in that episode of South Park where he is a deputy on a big wheel.

Shaq took the rock to the rack with authoritah.

with authoritah by fizzle April 10, 2004