Shrimp Sinigang
This soup is soured with tamarind, the pulp of long pods that grow on huge tropical tamarind trees. You can buy tamarind concentrate in jars, or tamarind pulp packed in chunks, in the Asian or Latin American section of large grocery stores, or in Filipino, Chinese or Indian shops. If using tamarind pulp, to make the equivalent of 1 tbsp (15 mL) tamarind concentrate, mix 2 tbsp (25 mL) seedless pulp or 3 tbsp (45 mL) seed-in pulp with 1/4 cup (50 mL) boiling water and strain, discarding solids. You can also use lime juice to sour the soup if tamarind is unavailable. The degree of tartness in Filipino sinigang broths varies quite a bit according to taste; feel free to add a bit more tamarind or lime juice if you wish.