Tamarindalso: มะขาม · me · imli
The sour fruit pulp from a tropical pod — Southeast Asia's primary acid before lime, and the soul of pad thai's sauce.
Origin
Native to Africa, naturalised across South and Southeast Asia for at least three thousand years. India, Thailand, and Mexico are the largest producers today.
What it tastes like
Sour with a date-like sweetness underneath. Less sharp than vinegar, less floral than lime; tannic on the back of the palate.
How it's used
Pad thai sauce. Massaman curry. Sambar in South India. The dipping sauce for som tam. Mexican agua de tamarindo. Worcestershire sauce in Britain.
Buying
Sold three ways: whole pods (best, most work), seedless block (most common, soak in hot water for 15 min), and tamarind concentrate (avoid — overly bitter, often too dark). The block, soaked, is the right format for nearly all recipes.
Substitutes
A 1:1 mix of lime juice and brown sugar approximates the sour-sweet character. Worcestershire sauce in tiny amounts adds the tannic note.
Storage
Block: dark cupboard, indefinitely. Pods: cool dark place, 12 months. Reconstituted paste: refrigerated, 2 weeks; frozen in cubes, 6 months.