Cut the mint leaves, soak them with 1 teaspoon of salt and water for half an hour; rinse and drain the water, distribute it in the ice cubes and fill it with water, and freeze into ice cubes.
Wash the Sydney with a belt core and cut into pieces. Add water and rock sugar to boil. Roll over medium heat for 10 minutes. After cooling off, cool and filter out the soup. Fill the container in the freezer and add mint ice.
Mint ice cubes are used in many ways to make cocktails, dilute juices or cool drinks; they are easy to make and use, and taste milder than squeezed juice.