Astragalus root is dried and sliced into long tongue depressor like cuttings.  A Traditional Chinese Medicine practitioner said to take six slices of the root and simmer them in two cups of water until there is one cup of liquid left.  Then consume water cold.  
Astragalus decoction described above can be used to make rice or used as a soup base.  I find this very comforting to my stomach.    

Root slices may be purchased in Chicago's Chinatown for about $6/pound (more).  Also, see Chinese Medicine.