This is a paste made from the seed of a tropical plant. It has the sweet and spicy flavour of soured date. Traditionally used for sambhar and rasal dishes in Europe we find it used in Worcester and HP sauces. Only a small amount need be used for a sweet and sour combination to be noticed. Pad Thai often includes tamarind for its tart and sweet taste with lime juice added for sourness and fish sauce added for saltiness and umami.