I find dried tamarind at Hispanic markets in the US, sold either in their pods or in blocks with seeds. I usually buy the blocks, so I have less work to do.
What do you need to make the pulp:
(About 2 cups of pulp)
1 (14-ounce) block of tamarind
2 cups of water
1. Place the tamarind block and water in a bowl
2. Let it soak for 20 to 25 minutes. Using your hands grab a handful of the tamarind pods and squeeze the pulp hard to separate it from the seeds.
3. Discard the seeds and keep the purée. Do this process until you have a thick and smooth pulp in the bowl.
4.Transfer to a glass jar and place in the refrigerator. To freeze the pulp, place it in ice trays.