How do you go about turning sunlight into jerky? Well, first off you have to be really bright. Sorry: that’s a Gnomish joke.
Truthfully, the stuff isn’t really sunlight itself; it’s a particular kind of dried meat from a particular kind of mountain squirrel that, when cut very finely with a particular sort of Gnomish knife during a particular sort of folk-magic ritual, can mystically absorb sunlight and retain it through the marinade and drying process. If you do it right, the stuff has a faint yellow glow in darkness, which is one way to tell if you have ‘real’ Sunlight Jerky. The other way, of course, is to feed some to a vampire, and see if he explodes.
Well, not exactly explode. It’s more like the vampire’s head will just catch fire from the inside, and pretty much keep burning for the next few hours. It’s still pretty dramatic to watch, although you probably shouldn’t do it on a full stomach.
Honestly, though, the primary reason why Gnomes make Sunlight Jerky is because it’s useful underground. It’s a non-flammable and persistent light source that is sufficient illumination for any number of underground-dwelling species, it keeps just as long as regular jerky, and it gives a very comforting sort of glow if you’re a member non-underground species. It’s also fairly tasty, if ever so slightly spicy. The vampire-ignition thing is merely a beneficial side effect. But it’s also a highly valuable one, which is why Sunlight Jerky costs an arm and a leg outside of Gnomish territories.
In Vampire country, it’s worth even more: basically, your life, if a bloodsucker catches you with any.