Put the pork in a large pan of cold water, bring to the boil and skim well. Simmer for 10 minutes, then add the onions, carrots, turnips and celery. Add the peppercorns and simmer gently for about 2½ hours.
To make the pease pudding, tie the soaked peas loosely in a muslin cloth and simmer in the pan with the pork for about 1½ hours. Remove from the pan and rub the swollen peas through