In a stand mixer with a dough hook attachment add the flour, water and salt and mix until a smooth dough has formed, roughly 5 - 6 minutes. For the best results, rest the dough for 30 minutes after this stage before rolling out, although this is not a complete necessity.
Meanwhile brown off the pork belly in a large frypan until deeply caramelised. Allow to cool while you roll the dough.
Turn the dough out onto a lightly-floured surface and then use a rolling pin to spread the dough out to 5mm thick. The dough needs to be large enough to full enclose the pork belly.
Cover the pork belly in spices and place fat-side down onto the dough. Pinch the dough edges together to enclose the pork belly, ensuring there are no holes or gaps.
Place the salt dough onto a lined baking tray and bake in your preheated oven for 3 hours before removing and allowing to cool for 30 minutes. Crack off the dough case and serve with your favourite condiments, this pork will make a delicious, tender sandwich meat.