1. Add half the salt to a large ceramic dish and lie the pork on top,cover with the remaining salt and refrigerate for at least six hours,or preferably overnight – you can do this in a large freezer bag,just make sure that you lie it flat in the fridge.
2. Cook the cotechino in a saucepan of simmering water for 40 minutes. Drain and set aside to cool.
3. Tip the lentils into a saucepan of simmering water,bring back to the simmer and drain.
4. Wash the salt off the pork and pat the meat dry. Place the pork,skin-side down,in a large,heavy-based,ovenproof pot and cover with cold water. Add the bouquet garni and simmer for an hour,skimming occasionally.
5. Preheat the oven to 170C fan-forced or 190C conventional.
6. After an hour,the liquid should have reduced by half. Add the stock and bring up to a simmer. Turn the pork over,add the lentils and simmer for about five minutes. Add the eschalots,garlic,carrot,celery,potato,celeriac and tomato,bring to a simmer and skim.
7. Cut the cotechino into two-centimetre slices and add to the pot. Cover with a lid or foil and place in the oven for 30 minutes. Remove the lid and cook for another 20 minutes.
8. Remove the pot from the oven and carefully lift out the pork. Slice the pork and return to the lentils. Serve directly from the pot with dijon mustard,freshly grated horseradish and buttered baguette on the side.
Tips
1. You can make this ahead of time,leaving the last stage in the oven until you're ready to serve.
2. A good dollop of garlicky aioli would be perfect with this.
3. Grill slices of baguette and serve on top of the stew.