Put the meat, the wine, the stock, garlic, onion, celery, bayleaves, cloves and peppercorns in a large pot and cover the meat with water until about 2/3. Bring to the boil. Turn the heat down and put the lid on the pan and simmer for about 1 hour and 15 minutes or until the meat is done.
Leave the meat to cool in the liquid for about 30 more minutes.
In the meantime prepare the tuna mayonaise by adding all the ingredients into a stickblender bowl and turning them until smooth.
Remove the meat from the liquid and cool.
Slice the meat thinly and arrange on a platter and spread the tuna mayonaise on top.
Garnish with parsley and capers and serve with lemon slices