Let the pork belly sit uncovered in the fridge for at least 24-48 hours to dry out the skin.
Mix the brown sugar, 2 tsp salt, garlic powder, and five spice to make the spice mix. Rub this mixture all over the pork belly.
Make a salt crust by mixing 1 cup of kosher salt with 1 egg white.
Place the pork belly on a baking sheet and cover it completely with the salt crust.
Cook the pork belly in the oven at 300°F for 1.5 hours.
Remove the salt crust, then brush the pork belly with the white vinegar and neutral oil.
Roast the pork belly at 450°F for 30-40 minutes or until the skin is crispy.
