I would like to disclose I have not been running the kitchen at Side Chick for several months now as I embark on other projects, therefore I have no influence on the quality of food anymore. While I’d love to find a new venue to pursue perfecting chicken rice I have nothing planned for now.
Only one place in Hong Kong that I know of uses the hawthorn (3 types: fresh fruit, haw flakes like in the candy, and dried hawthorn sticks, in addition to the typical ingredients) for their nuanced sweet and sour pork, Tak Lung in Sun Po Kong, and they use pork belly I believe instead of pork shoulder.
The pickled sour plum addition for sure is part of the recipe at Luk Yu Tea House (Hong Kong) but it’s such a small amount.
Using hawthornes and pickled sour plum might be a bit overkill if it’s not controlled properly.