This is a delightfully sweet and tangy snack or side dish made with chickpeas and potatoes. Tamarind paste is readily available in Indian grocery stores. Update based on a review - Shallots can be substituted with mild onions and is meant to be raw. This imparts a special crunchy flavor that is excellent in all Indian chaat and some Indian salads. Also remember that tamarind is a distinctive taste and if you're new to it, start with less and go by taste. Experiment and enjoy!