dry roast the cumin seeds till they start to burn and turn black.
allow to cool and ground to a fine powder. keep aside
in a small blender take fistful of mint leaves and coriander leaves.
make a smooth puree / paste adding required water. keep aside.
now in a large jug, add few ice cubes.
grate the ginger
now add coriander - mint puree to it.
add roasted cumin powder
next add some amchur powder
followed by black salt. you can also replace with salt.
add 2 glass of water and squeeze some lemon juice.
now add crushed black pepper powder.
give a good mix and check for seasoning.
transfer to serving glass or jar and drop few ice cubes just before you serve.