Boil water together with bonito granules. Add miso paste, stir till dissolved and add in tomatoes. Simmer for about 15 minutes in low heat. **Add in shrimps and boil the soup for about 2 minutes just before serving.In another pot of boiling water, blanch udon for 2 - 3 minutes, drain well and divide into 2 - 3 serving bowls. Blanch xiao bai chai for 1 minute, drain well and divide/distribute into the serving bowls Lastly blanch the pork belly for about 2 minutes or till cooked and also divide/distribute into the serving bowls. Lastly pour the hot soup into the bowls of udon together with the mushrooms and shrimps. Serve immediately.