Pig trotters with ginger and vinegar

Ingredients:
1.2kg old ginger
1 bottle (750ml) of Chan Kong Thye black rice vinegar (it has a picture of a dog on the label with the words 'double ingredients' in Chinese)
3.75l water
500g black sugar
2 pig trotters
1 tsp sesame oil

Method:
1. Remove skin of old ginger and wash. Drain well.
2. Heat wok, add sesame oil slowly and fry ginger until fragrant. Add water, vinegar and sugar to boil, then simmer for about two hours. Leave aside to cool.
3. After a week, boil it, then simmer for an hour every day for six days for fuller flavour. Remove ginger.
4. Blanch trotters in boiling water for about five minutes and place them in vinegar stock. Bring to a boil, then turn down the heat and simmer for about 45 minutes.
5. Turn off the heat and put ginger back. Let it boil once more. The trotters are best eaten the following day.