Next day, take the pork belly out of the fridge. Pre-heat the oven to 160 C fan-forced while the pork belly comes to room temperature.Pat the top of the skin dry if you see moisture on top. If some salt gets removed, that's ok! Place about 1 tbsp of neutral flavoured oil on the skin and spread around just on the skin.
In an oven tray, place about 5 star anise and pour in roughly 500-700ml of hot water from the kettle. The quantity doesn't matter, you just want to not have the water dry out as you cook. On a rack, place the pork belly on top, not touching the water. Check the pork from time to time and if the water has dried up, pour in more hot water.
Place the tray of hot water and pork belly in the oven, uncovered and roast for 1.5 - 2.5 hours. See notes re: cooking time.
After roasting, turn the oven heat up to 230-240 C (depending on how hot your oven can go) and roast on high temperature for about 20 minutes, checking the colour through the oven door to ensure it doesn't burn. It can take less or more time depending on how dry the skin got.
Once the skin has bubbled, become golden and crispy, remove the pork out of the oven and leave to rest at least 30 minutes.
Chop and serve. Tip cut so the crispy skin side is on the board, slice through the meat and use the force of your palm against the knife to force the knife through the crispy skin.