This superb Lincolnshire dish of salt pork filled with herbs is known as stuffed chine. Verlaine, in the mid-1870s, spent a year as a schoolmaster just north of Boston. He liked chine so much that he tried to find it elsewhere in England, but without success. Verlaine's chine was stuffed with leeks, spring onions, lettuce, raspberry leaves, parsley, thyme and marjoram. Nowadays parsley suffices, but you will need a great deal.
1 Chine of pork large bunch Fresh parsley
Take a careful look at your piece of meat. One side will be bordered with fat, the other will show the backbone. Turn the fat towards you, the bone away, with the lean side uppermost. Leaving a border of meat, make a deep slash from fat to bone (not to the edge of the joint but to the fat at the edges, leaving a pocket for the stuffing). You will not go through, as there is the unseen barrier of the vertebrae wings of bone.
Repeat, make five slashes in all. Turn over and do the same the other side. Soak the meat for 24 hours.
Meanwhile prepare an enormous chopping of parsley, and other greenery if you like. Use a processor, but do not reduce to a soup. A moist hash is easier to stuff than a coarsely chopped dry pile of parsley. Cram as much as you can into the slashes.
Tie the chine tightly into a cloth. Put into a pan, cover with cold water, and simmer for four hours. Change the water as it becomes salty. Cool in the water for two or three hours, remove, drain and press under a weight, with the meat still in its cloth.
To serve, unwrap the chine, and slice it form the fat end, parallel to the fat. The slices tend to fall apart, but reassemble them on the plate. In Lincolnshire you eat stuffed chine with vinegar, but vinaigrette and salad with bread and butter and mustard seem better to me.