Dry roast the cumin seeds in a pan till they start gving off an aroma. Do not let them darken. Cool and pound/ grind into a somewhat coarse powder. Pound and grind the fennel seeds and the black peppercorn as well.
Put the mint, coriander, ginger and the lemon juice in a blender or the chutney jar of your mixer/ grinder and grind into as fine a paste as possible. Add a few tsp of water if necessary while grinding.
Put this paste in a large jug or pan, add the chilled water, the powdered cumin, fennel and peppercorn, the black/ rock salt, mango powder, sugar and salt to taste. Stir the mixture well and strain to remove the solid particles.
Pour into serving glasses. Garnish with the boondi and slices of lime and mint leaves (optional). Serve chilled immediately. Jaljeera is best made and served fresh. Do not keep this in refrigerated for more than a couple of hours as the colour of the Jaljeera tends to become darker and the freshness of the spices disappears.
Server chilled garnished with boondi.