Put the pork hocks in a large saucepan and add the water. Bring to the boil and cover. Simmer 1½ hours.
Remove the pork from the saucepan and skim off any fat. Add the lentils and salt. Bring to the boil and simmer, covered, about 25 minutes, or until tender. It may be necessary to add more water to the saucepan. The lentils, as they cook, should be almost but not