This is a delicacy that's a popular item at most Chinese banquets. The chef will cook it by skewering a small piglet, spread-eagled on a pitch-fork, and roasting it slowly over a fire.
The seasoning is a secret, and it varies from chef to chef. You will find subtle differences in China, Taiwan and Hong Kong. You will also need ten years of apprenticeship under a master chef before he will consent to pass on his own secret recipe. That is if he doesn't die first. If you're non-chinese, aka ang-moh, it will probably take you 20 years to discover the secret. Plus, you'll probably have to marry into the family.
The dish will be served with the now roast-red piglet cut into little rectangles. But, do not make a move. Wait for the waiter to place a small rectangle of crisp roasted bacon on to your plate. There will also be a plate of egg-roll skins, thin as lace, and probably some slivers of cucumber, and what looks like a platter of dark barbecue sauce.
Slowly, gracefully, use your chopsticks to lift a thin layer of egg roll skins off the common platter, and on to your plate. Do not do this by skewering the lot with your chopsticks. You will set Western civilization back by at least a thousand years by this serious breach of etiquette.
Next, use a spoon to ladle a small amount of sauce onto the egg roll skin. Use your chopsticks to put the cucumber and the piglet skin onto the egg roll skin. Now, put down your chopsticks, and use your fingers to gently roll the concoction on your plate into a small cigar. Tilt your head back slightly, and bite into the cigar, letting any sauce flow gently into your mouth. Try not let the sauce dribble down the side of your mouth and over your chin.
You will also find a small bowl of clear liquid with a luscious slice of lime at the bottom. After this admirable performance, do not spoil it all by drinking the bowl. It is not a soup. Dip your fingers into it, and then dry them on your towel, and enjoy the approving glances of your Chinese hosts.
Top tip: if there is an unwary ang-moh next to you that you want to show up, when he is not looking, quickly wash your fingers in the bowl, and then let him drink it.