Put juniper berries in a mortar and crush them roughly. Together with peppercorns, coriander seeds, cardamom and cinnamon sticks, roast briefly in a pan without fat. Remove from the pan immediately and let it cool down.
Wash lemon and orange hot and rub dry. Peel off about half of the peel as stiffeners (without white skin). Wash rosemary, bay leaf and ginger and dab dry. Cut ginger into slices (do not peel).
Put the roasted spices, lemon and orange peel, rosemary, bay leaf and ginger with the vodka in a large screw-on glass. Close it and let it steep for about 3 days. Then filter through a fine sieve.
To serve, fill tall glasses to about 2/3 with ice cubes, pour 50 ml gin into each glass. Top up with tonic water. Enough for about 15 glasses.
Preparation time approx. 20 minutes. waiting time approx. 3 days