Serve these tasty sosaties over rice and chopped fruit such as banana or mango. The marinating time is at least overnight and up to 3 days, plan accordingly. You can also use beef or pork (pork is totally non-traditional) for this recipe. You can use the lemon water as a substitute, however Tamarind is traditionally used in this recipe to add a sour note to balance the sweet flavour. The easiest way to buy tamarind is in cans (Goya) in the Mexican Food section. But it is also sold in packets as a pulp, it looks like pulped dates. You will not be using the pulp, but water made from the pulp. Soak about 100 grams of pulp in water for 10-20 minutes. Squeeze the tamarind pulp with your hand to squeeze out the sour juices. Use the water and keep the pulp in the fridge to reuse. You can reuse the pulp several times until it loses it sourness.