DAY 1: Mix salt, sugar, peppercorns, 2 cloves garlic and 2 sprigs thyme together in a large bowl and add 1 cup of very hot water. Stir until sugar and salt dissolve. Mix in 2 litres of room temperature water. Place pork belly in a deep baking dish and pour this brine mixture over. Cover and refrigerate overnight.
DAY 2: Preheat oven to 150°C Heat oil in a large heavy-bottomed saucepan over medium-high heat. Sweat carrots, celery, leek and 2 cloves of garlic for 5 minutes. Season lightly with salt and pepper. Lower heat to medium, add wine and cook for another 2 minutes. Add 1 1/4 litres of stock, tomatoes, bay leaves and 2 sprigs thyme and bring to a simmer.
Remove pork belly from the brine, rinse with clean water and place in a deep casserole dish or Dutch oven. Pour over the hot stock and vegetables. Cover with a lid and cook in oven for 2½ hours or until tender (taking care not to overcook and dry out the pork).
Meanwhile, bring a large pot of salted water to the boil and cook sprouts for 3-5 minutes or until just tender and bright green. Drain and cool in a large bowl of ice water. Dry on paper towels, cut in half and reserve.
Once pork is ready, remove from oven. Carefully remove from the braising liquid onto a flat tray. Place another flat tray on top of the pork with 4 or 5 heavy tins on top to press the pork into a flat, even shape. Refrigerate in this position for at least 1 hour and completely cooled.
To score the pork: Remove and use a large sharp knife to lightly trim the edges of the pork into straight sides. Cut into 4 equal pieces and score the top of each piece into a 1cm-wide diamond pattern.
While the pork is cooling, make the polenta. Place remaining stock, bay leaf and thyme in a medium saucepan over medium-high heat. Bring to a simmer, then remove and discard herbs. Slowly pour in the polenta, whisking continuously. Reduce heat to medium and bring to a gentle simmer. Carefully whisk continuously for 7 – 10 minutes or until tender and thickened to the consistency of creamy mashed potatoes. Then add Parmesan and butter, mix well and season to taste. Remove from heat and cover.
Cook honey, soy, ginger and star anise in a small saucepan over a low heat for 5 minutes. Strain, reserving liquid and star anise and discarding other solids.
Preheat oven to 200°C.
Heat a large nonstick frying pan over low heat and place pork into the pan, scored side down. Cook for 7-10 minutes or until the fat has rendered, skin is golden brown and starting to crisp. Transfer to a baking sheet, scored side up, and baste on top and sides with the glaze.
Cook in oven for 15 minutes or until the glaze has caramelised and the pork is heated through.
Return the same frying pan with leftover fat to a medium-high heat and cook apples and sprouts for 3-5 minutes until they start to brown. Add remaining glaze and cook for another 6-8 minutes until tender, well glazed and heated through.
Heat the polenta over medium heat, with a little hot water if necessary, stirring until creamy.
Arrange the polenta, pork belly, sprouts and apples on 4 plates and drizzle with remaining glaze from the pan. Garnish with star anise and serve. (Do not eat the star anise.).