By Merrilees Parker
Widely used in regional Chinese cuisine, this is a sauce made from fermented, salt-preserved soya beans. It is a cooking sauce rather than a table sauce or condiment, and has a subtle, deeply savoury taste. The soya beans used in blackbean sauce may be black or yellow; the sauce’s colour is a result of the beans becoming dark due to the enzymes released when they are dried at high temperatures during the fermentation process.
Blackbean sauce comes in jars, cans and vacuum packs and is sometimes flavoured with garlic, ginger, chillies or spices. Do not use blackbean sauce interchangeably with yellow bean sauce, which will give a different flavour and colour to your dish.
Unopened, blackbean sauce will keep well for several months.
Use in Chinese stir-fries and steamed dishes, and add towards the end of cooking. The sauce is often combined with tofu, beef, or green peppers.
Source and Credit by: http://www.bbc.co.uk/food/blackbean_sauce