Rinse the basil and grind it with the help of a mortar (if there is no mortar, the basil can also be chopped up).
Put the basil in a jug. (It has to be heat-resistant!). Peel the ginger, cut into small cubes and add. Bring the water to the boil and add to the jug along with the sugar. Squeeze the lemon and pour the juice into the jug.
Let the drink cool down and enjoy ice cold. Especially refreshing on hot summer days.