A green mango is essentially an unripe mango--so it will be more sour than sweet. Look for roasted ground cumin in your grocery store or toast and grind your own cumin seeds. Fine Indian black salt (kala namak) is a pungent-smelling lava rock salt that packs a ton of umami so a little goes a long way. Made by evaporating cane juice, jaggery can be found as a powder or more commonly in clumps. Black Chickpeas (kala chana) are a rare variety that are smaller and slightly nuttier than regular chickpeas. Pani Puri are crispy shells, shaped like ping-pong balls. All of the above can be found in Indian food markets.