Place the green lentils in a large saucepan and cover with water; bring to the boil and simmer for about 25 minutes or until just tender
Remove the skins from the sausages and crumble the meat into a nonstick frying pan, brown the meat and set aside
Heat the oil in a large saucepan, add the celeriac, carrots, parsnip, chilli and fennel seeds and cook for 10 minutes, covered, until tender – stir now and then
Add the lentils and stock, and bring to simmering point
Add the kale or cabbage and simmer together for a few minutes until tender; season to taste
Add the browned sausage meat to the soup and heat through, ladle into heated bowls and scatter with the parsley leaves; serve with the feta fritters
Mix all the ingredients for the fritters in a bowl; heat the butter in a frying pan and when sizzling add teaspoonfuls of the batter; turn the fritters over; they will need only about 45 seconds to 1 minute on each side
Transfer to some kitchen paper; keep warm and serve with the soup
6 servings