Wear gloves and clean the work area thoroughly
Sort the chitterlings and discard any damaged pieces or debris
Rinse under cold running water several times
Turn each piece inside out if needed
Scrape away fat, membrane, and any remaining waste
Soak in cold water with salt or vinegar
Drain and rinse again
Repeat rinsing and cleaning until water runs clear
Place in a large pot and cover with fresh water
Add onion, garlic, salt, and seasonings if desired
Bring to a boil, then reduce to a simmer
Skim off foam and impurities as they rise
Simmer until tender, usually several hours
Drain and rinse once more after cooking
Season and serve hot