Put the garlic, pickling spices, and leaves and peppercorns into a mortar and crash coarsely.
Put into the dish together with the sugar, Saltpeter, and salt. Add the meat and turn the coat with mixture rubbing it well into all the surfaces of the meat.
Finally add cold water to come just at the top of the meat
Refrigerate for 14 days
TO COOK: Take the meat from the liquid and wash well. Pour out the liquid from the dish and put back the meat into a large container. Cover with cold water, bring slowly to the boil. Remove all the scum with a spoon dipped in cold water. Now add the large onion, celery, carrots, cinnamon, mixed spice, salt, a half teaspoon allspice, half teaspoon mustard seed, two bay leaves, a few grinds of black pepper and three cloves of garlic.
Cover and simmer very gently for 2-3 hours.
Serve hot then when cool take the remainder, place into a bowl put a plate and a weight on top and let stand for 2 or 3 hours. This will compact the meat and make it super easy to carve for sandwiches in the days ahead - if it lasts that long!