A taco hole can be any number of things. It can be a space into which tacos are inserted, such as a human mouth or cardboard tray. It can be a place from which tacos are dispensed, like a window in an alley adjacent to your favorite bar.
In this case, taco hole is simply a cognate and nom de blog for “Troy Coll,” the author of this website. He is a freelance writer, an ambitious home cook, and an advocate of human flourishing.