Tamarind is widely used thorough the world, but relatively unknown here. But you have almost surely come across it, because it is a central ingredient in Worcestershire sauce.
The tamarind is the fruit of a tall tree that grows in Asia and North Africa. Its pods are about five inches long and contain seeds and a pulp that become extremely sour when dried. Tamarind pulp concentrate is widely used in Indian and Middle Eastern cooking. Someone once said, "Tamarind pulp is to East-Indian and Middle-Eastern cuisine what lemon juice is to Western cuisine." OK, that may not be the catchiest line ever uttered, but tamarind flavors many curries, chutneys, lentil and bean dishes, and is often used in hot and sour soups.
Some have compared the taste to that of sour prunes. Some cookbook authors, not knowing of your honest desire to cook well, will let you substitute lemon juice for tamarind, but you should not do it.
Tamarind can be found in various forms - concentrated pulp with seeds, a canned paste, whole dried pods, or powdered - and is available in Indian and some other Asian markets, and available in syrup form in a broader selection of markets. There is a wide variety of tamarind products available online, including:tamarind pods seedless dried tamarind tamarind concentrate tamarind puree tamarind syrup tamarind dipping sauce tamarind nectar tamarind candy
See, there’s a whole world of tamarind out there for an adventurous guy like you to explore!