Cut pork into 2 equal pieces and place onto a large baking tray along with the Hoi Sin Barbecue sauce and star anise, massaging the sauce into the meat before covering and allowing to marinate for at least 2 hours or overnight in the fridge.
Remove the pork from the fridge at least 1 to 2 hours before you roast.
Pre heat your oven to 200c. Uncover the pork, add 1 ½ cups of water and mix into the marinade that will have pooled on the tray and place on the middle shelf of the oven to roast for 25 minutes. After the first 25 minutes, turn the pork over and baste. If the marinade is looking dry you can add more water to loosen, then cook for a further 20 minutes and repeat. Cook for a final 10 minutes or until the pork is cooked all the way through and has achieved a nice caramelised crust, which adds colour, flavour and texture.
Set to one side and allow the meat to rest for 20 minutes, ensuring you reserve some of the marinade at the bottom of the baking tray, discarding the star anise.
Once the pork has rested, cut 1 ½ cups of the pork into ½ cm cubes and place into a bowl, adding 3 tbsp. of the reserved marinade and mixing well.
Roll out the pastry leaving it laying on the grease proof paper it was rolled up in and using a round cutter (approximately 8cm in diameter), cut out pastry discs. Place 1 to 2 tbsp. of pork filling into the centre of each disc and carefully pull up the sides, pinching the pastry at the top to seal in the filling. Repeat until all of the pastry has been used. Pre heat your oven to 200c and then placing your puffs on to a baking sheet, brush each puff with the egg and water wash. Place into the oven and bake for 15 minutes. Can be served hot or cold.