Roasted green mango cooler (Aam panna)

1. Wash the green mangoes and boil them in a pan with enough water to cover for 20-25 minutes until the skins split and the flesh is completely soft. (You can also roast them directly over a gas flame, which gives a smokier flavour.)

2. Let them cool, then peel off the skins and scrape the soft, yellowish flesh off the stones into a bowl with a spoon.

3. Dry-roast the cumin seeds in a frying pan for 1 minute until fragrant, then grind finely in a mortar.

4. Put the mango flesh into a blender with the sugar, roasted cumin, black salt, mint leaves and 200 ml water and blend until completely smooth. This is the thick panna base.

5. Dilute with the rest of the cold water, taste and adjust with sugar or black salt: it should be pleasantly sweet, sour and salty.

6. Pour into glasses filled with ice, garnish with a mint leaf and serve well chilled.

Tip: North India's traditional summer drink, drunk to ward off the "loo", the scorching hot wind: the salt and sugar replace the minerals lost through sweating. The thick base keeps for a week in the fridge; just dilute it before serving.