Oyster sauce

Interestingly, this is one of the easiest ingredients to find a vegetarian substitute for, as the company who first made oyster sauce now make a vegetarian version as well. It is often sold as ‘vegetarian oyster sauce’ in Asia, but in the UK and Australia, it is often just called ‘vegetarian stir-fry sauce’ or ‘mushroom sauce’. The brand you are looking for is Lee Kum Kee, and you should be able to find it at most major supermarkets. If all else fails, just fry some mushrooms and keep the liquid they release as they cook, then use this in place of oyster sauce, adding a pinch of sugar as well.