Napa Cabbage Soup with Daikon Radish and Bamboo Shoots

I originally created this recipe for cooking winter melon because winter melon and bamboo shoot soup is one of my favorites. But winter melon can be hard to find, even at some Asian markets, so I tested the soup with different vegetables. The combination of Napa cabbage and daikon radish turned out well and stayed true to the spirit of the winter melon soup that I love. If you happen to find winter melon, feel free to replace the daikon radish and/or Napa cabbage with it.