There are a few things to consider when preparing this dish: Firstly, a mix of sour black vinegar and sweet black vinegar are used; next, either young or old ginger can be used, though old ginger is preferred when cooking this dish for post-natal consumption. The secret ingredient in Crystal Jade Kitchen's recipe are brown sugar slabs. The brown sugar adds a rich caramelly taste to the braising sauce.
Another trick is to chop up the trotters into smaller chunks so it is easier to eat afterwards, and also absorbs the braising liquid better. You can add other ingredients such as hard-boiled eggs towards the end of the braising time.
Here is Crystal Jade Kitchen's recipe for pig trotters in vinegar:
2kg of pork trotters
2 tbsp sesame oil
500g old ginger, cut into chunks and lightly smashed
350g brown sugar slabs
750ml black vinegar
2.5 litres (or one 3kg-bottle) sweet vinegar (Try Tim Ding's)
1. Blanch the pork trotters in a pot of boiling water for 2-3 mins.
2. Saute the old ginger in sesame oil over medium heat for about 4-5 mins until fragrant and add the brown sugar.
3. Pour the two types of vinegar into a large pot and add the pork trotters. Bring to a boil and simmer on medium-low heat for about 1-2 hours, till the trotters are tender.