1. Soak the haricot beans in cold water overnight.
2. The next day, put the bacon hock into a deep pan with 2 litres of water. Bring to the boil over a medium heat, then cover and leave to simmer gently for 45 minutes to 1 hour, turning it over now and then as the liquid starts to reduce, until the meat is tender and falling away from the bone. Leave the hock in the cooking liquor until cool enough to handle.
3. Meanwhile, drain the beans and put into a second pan with 1 litre of cold water. Bring to the boil, skimming off any scum as it rises to the surface, then lower the heat, cover and leave to simmer for 45 minutes to 1 hour, until tender. Drain and set aside.
4. Heat the oil in a large pan over a medium heat. Add the onion and cook for 10 minutes. Add the carrot and cook for 5 minutes until it’s soft. Strain 1.75 litres of the bacon’s cooking liquor into the pan, add the turnip or swede and potatoes and simmer for 10 minutes.
5. Meanwhile, discard the skin from the hock and tear the meat into small, bite-sized pieces.
6. Quarter the cabbage, remove the core and thinly slice (or slice the curly kale). Add the bacon pieces, cabbage and beans to the soup and simmer for 5-7 minutes until tender.
7. Take the pan off the heat and stir in the garlic, parsley and plenty of black pepper. Ladle into large warmed soup plates and serve with lots of fresh crusty bread.