Use a spice grinder or coffee grinder to powder the Sichuan chillis, cinnamon, cloves and star anise. For the cinnamon I use a rolling pin to break it up a bit first.
Combine the sugar, salt, curing salt and all the spices ... I use my KitchenAid to make sure they are well mixed.
Cut the pork loin into two equal pieces, and divide the curing mix in two as well.
Using either ziplock bags or a vacuum sealer, put 1/4 of the cure into the bag, lay one of the loins pieces onto the cure, and then spread the next 1/4 of the cure on top. It is a bit fiddly in a bag, but rub the cure in so all parts of the meat are covered. Then make sure there is a pretty even spread of cure, top and bottom. wipe the mouth of the bag to remove curing mix ... or it will be hard to seal the bag. For a ziplock, remove excess air and seal ... if you are using a vacuum sealer then you will be removing all the air :-)
Repeat for the second piece of loin.
Place in a fridge for 7 days, turning the meat every day.