The Enlightening presents a toroidal, or, more colloquially, doughnut-shaped black hole structure. The plasma jets commonly observed are generated by gravitational field lines which draw matter from the inner walls of the torus and expel it back out into space in the form of plasma, via twisting magnetic field lines extending through the central opening of the torus, in this view. The black hole itself is torus-shaped, with additional circular, twisted magnetic field lines above and below the torus, parallel with the plane of the accretion disk. The central field passes through the center of the two circular fields, as well as through the opening in the black hole.
The stance in the book that the black hole itself is a superconductive, superfluid material, which helps generate the massive magnetic fields required to expel material in the form of plasma, via the jets.
Here is an article from everythingselectric which also postulates a very similar toroidal structure for black holes.
I like it!