Quantum Tunneling

"Inconstant Star," Chapter X.

"Quantum tunneling causes [mini-black holes] to give off particles, matter and antimatter, which mutually annihilate." (p. 241)

I have googled Quantum tunnelling but do not understand the technicalities. Does it mean that, although matter inside the event horizon of a black hole would need infinite energy to accelerate past the event horizon, it can nevertheless tunnel through it? Thus, matter would escape? How would this relate to the matter being mutually annihilating matter-antimatter pairs?

This sounds similar to, if not identical with, Hawking radiation although I thought that the latter occurred when a matter-antimatter pair appeared just outside the black hole so that one fell in whereas the other escaped. This also is thought to reduce the black hole somehow.

(Reading the Hawking radiation Wikipedia article partially clarifies these issues.)