Tamarind paste

This tangy, slightly sweet pulp is used in India, Thailand, Malaysia and Singapore to add acidity. I like to use the paste as it is easy to work with, but if you can only find it in block form, tear off a chunk, soak it in a little hot water for about 5 minutes and then strain the pulp to remove the seeds. You can usually find tamarind paste in supermarkets, but if not, you can substitute it with twice the amount of lime or lemon juice and a pinch of brown sugar.