Cut the pork skin into 4 pieces. It will cook more evenly and be easier to clean later on.
In a large saucepan over medium heat, bring 4 quarts water to a simmer. Add the skins and cook for 1 hour, or until they are soft and somewhat gelatinous.
Preheat the oven to 300 degrees F.
Remove the skins from the water with a slotted spoon and put onto a large plate. Discard the liquid. Let the skins cool in the refrigerator for at least 15 minutes so they will be easier to handle.
Put one of the pieces on a cutting board skin-side-down. The other side will have bits of meat and fat on it that will have turned white during cooking. With a very sharp chef's knife, slice as much of the meat and fat off as possible, leaving only a thin piece of skin. Be careful not to slice into the skin underneath. The cleaner you get the skin, the crispier the crackling will be when fried. Repeat with remaining pieces.
Arrange the skins on a parchment-paper or Silpat-lined sheet tray and put in the oven for 1 1/2 hours. Flip the skins and continue cooking for 1 1/2 hours, or until the skins are completely dry. Remove from the oven and let cool.
When cool enough to handle, scrape off any remaining bits of fat and meat. The back of a knife works well for this. At this point, the cracklings can be stored in an airtight container for up to 1 week.
Heat about 4 inches of oil in a deep-fryer or pot to 350 degrees F. Break the cracklings into small, inch-sized pieces. Fry in batches for 30 to 45 seconds, until crisp and puffy. Remove from the oil and season with salt. Serve immediately.
Recipe from Michael Symon's Carnivore: 120 Recipes for Meat Lovers. Copyright (c) 2012 by Michael Symon. By arrangement with Clarkson Potter, a division of Random House, Inc.