
You pan-toast something by cooking it in a frying pan or a wok with no fat.
You can, for instance, pan-toast breadcrumbs. (Why pan-toast them instead of toasting them in your toaster oven? Better control, easier to spread them out fully, a fun job to give somebody else while you're putting another dish together ... or, really, go ahead and toast them in the toaster oven.)
But supposing you do want to pan-toast your breadcrumbs, you put them in a cold frying pan, put the pan over a brisk flame, and stand there (not stirring) waiting for them to start to smell toasty. When the smell changes to a toasty smell, you can swirl the crumbs around in the pan once, but then remove the pan from the flame and the breadcrumbs from the pan immediately. Do not stand there smelling and stirring, smelling and stirring, or you will surely burn the whole panful.
In pan-toasting you judge doneness by smell. If you wait till the stuff you're toasting changes color, you have waited too long, it's burned.
Other things you can pan-toast are nuts and whole spices.
You can't pan-toast things with a high moisture content, like fresh vegetables; the outsides will scorch before the insides cook. You can pan-toast dried vegetables like nori (seaweed) or sun-dried tomatoes (the kind that come dry, not the kind in oil) or dried mushrooms, but it's an unusual thing to want to do.