In a mortar & pestle, add mint leaves along with the lemon wedges and ½ teaspoon sugar and crush until the juices are released.
In a bowl, add the crushed mint leaves, lemon juice, sugar, salt, water/soda along with chaat masala and mix well. Check for the sweetness and add sugar if required. Filter out the mint leaves.
Pour into serving glasses and drop some crushed mint leaves along with lemon slices. Add ice cubes. Decorate with a lemon slice and fresh mint leaves on the side.