WHAT IS IT? I hope you have a strong stomach, as caul fat is the fatty membrane surrounding an animal's internal organs. In this case a pig. Forget kevlar or kryptonite, it is one of the weirdest substances I have encountered. It comes vacuum packed looking like a large lump of chewing gum. It actually has properties more akin to a pair of fishnet tights. When you unravel and stretch it is stretchy, lacy and almost transparent. If you can overlook the slight offaly smell, it is actually quite pretty.
WHAT DO I DO WITH IT? It is traditionally used to wrap terrines, pates and faggots. Anything that needs a bit of support while it is being cooked. To use another undergarments analogy, it is basically spanx for meat, holding everything together and making it look better while ultimately being invisible. The caul fat dissolves during the cooking process - as fat is want to do. Caul fat also has the added advantage - also not unlike spanx - of keeping everything encased within it moist.
I would put my head above the parapet here and say that I would choose caul fat over bacon for wrapping a terrine. I used it to wrap a haslet (more on this to come), but it would also be good round a burger or meatloaf-type thing.
WHERE CAN I GET IT? A good butchers, or you can order from Turner and George
online. Like other offal-y bits, it is cheap as chips so no excuse to go get some spanx for your next faggots.