Make sure the pork belly is very cold. Using a sharp knife cut lots of little cuts in the skin in a crisscross pattern. Combine the salt, pepper and baking soda in a small bowl. Rub the whole pork belly with the mixture but focusing mostly on the skin side of the pork belly. Let the pork belly sit on a rack in the fridge for 8 hours or overnight.
Preheat the oven to 350. Remove the pork belly from the refrigerator and rinse off the salt/baking soda slurry. Pour the rice vinegar on the skin to ensure that the baking soda is gone. Place the rosemary and thyme on a baking sheet and top with the pork belly ensuring that the skin side is up. Put the pork in the oven and cook for 1.5 hours. After 1.5 hours remove the pork belly from the oven and increase the oven heat to 425. Put the pork back in and remove it after about 15 minutes or when the skin in puffy and crispy. Allow to cool.
For the chutney, place all the ingredients into a medium or large sauce pan. Turn the heat to medium high and bring to a boil, stirring occasionally. Reduce the heat to low, cover, and let the chutney simmer for 30 minutes until the fruit has softened and broken down. Uncover and let simmer another 10 minutes or until most of the liquid has evaporated and the chutney is nice and thick. Cool completely and then transfer to a storage jar or container. To finish, carefully slice the pork belly into portions and top with the chutney.