Preheat the oven to 325 degrees F.
Grind the fennel seeds, peppercorns and salt in a spice grinder. Place the pork shoulder into a roasting pan and cut the rind into cross hatches. Rub the spice mixture into the meat and put it in the oven for 4 hours.
Arrange the potatoes around and under the meat and put it back into the oven for 1 hour.
Now add the garlic, shallots and carrots around the pork. If your roasting pan is not large enough to accommodate all the vegetables, place them in a separate roasting pan. Cook for 30 minutes, then add the pears. They don't need much cooking time and will disintegrate if cooked too long. Cook for another 30 minutes
When the meat is tender and flakes with a fork, remove it and the vegetables and keep warm. This will give the pork time to rest and become more tender. If the pork rind is not crispy, put it under the broiler for a few minutes until it is really crunchy and crispy.
To make the gravy, pour off all but 1 tablespoon of the fat from the roasting pan. Stir the flour into the roasting pan, add the wine, put the roasting pan onto a burner over medium-high heat and cook until the wine is reduced by half. If not using the wine, do this with the stock. Now add the stock and scrape off any bits of meat and vegetable on the bottom of the pan. Taste and add any seasoning if you think it needs it.
If the gravy is too thin, make a paste in a bowl with 1 tablespoon and 1 tablespoon flour. Add some of the hot gravy to the small bowl and stir. Add this to the hot stock, stirring constantly and bring to a boil. The gravy will thicken slightly.
If your gravy is too thick, just add a touch more stock. Serve the meat and vegetables with the gravy.
This dish struggles to make it to the table as the family descends upon it while I am trying to finish the gravy! Use any leftovers for pork sandwiches with some crunchy pickle.