Sugar and Vimto.
To make tamarind juice, soak some tamarind.
Then squeeze out the juice and discard any unwanted seeds and parts.
Next add some vimto to the juice.
Then add some sugar to taste.
Instead of adding plain sugar, you can make sugar syrup by simply cooking sugar and water.
Let the syrup cool, then add it to the juice, mix the juice and serve cold.
Adding syrup makes the juice taste better than just adding sugar.