Drain the sour cherries, pour rum over them and let steep for 3 hours. Peel the ginger and cut into fine sticks. Pour the fruit tea bag together with the cinnamon stick, ginger, star anise and cloves with 0.7 l of boiling water and let it steep for about 8 minutes. Heat the cherries and rum in a saucepan, but do not boil. Remove the tea bags, pour the fruit tea with the rum cherries into glasses and serve immediately. If desired, sweeten with rock candy.