6-7 slices Chinese licorice (gan cao)
2 L water
Rinse herbs off any grit and dirt. Put them into a pot of boiling water. Simmer for 2-3 minutes and then turn off the heat. Let steep for 10 minutes or so in the hot water. Strain and serve with rock sugar.
I didn't add sugar to mine because I was told that would generate more phlegm. It was very soothing for the throat and very refreshing even without the addition of rock sugar.