Plasma Jet

how do black holes emit jets?
my understanding of black holes is that there gravity is so great not even light can escape so how is it possible for them to emit jets of plasma!?
The black hole rotates and as it does, it would be like north and south poles of the magnetic field it generates on the very rotational axis. I would say plasma vortices occur at the polar regions of the BH. And this plasma has not entered the black hole and can not perhaps because of distance from the BH, where the gravitational tides may be weaker (?).
The BH influences the plasma to a degree but the furthest away stuff is excited by vortex action, and it is shot away from the source(?)
Of course, any strong vortex, is going to move matter away, due to the suction/helicoil action of it. And since this vortex is made up of energy, that energy is going to move at the speed of light or similar.