To make the mushroom dumplings, heat the oil in a non-stick frying pan over high heat. Add the mushrooms, galangal, chili and garlic and cook for 2 minutes. Add the soy, vinegar and kecap manis and cook for a further 2 minutes. Remove from the heat and stir through the coriander. Set aside to cool completely.
Place the wonton wrappers on a clean bench top dusted lightly with rice flour and brush the edges of the wrappers with water. Place 2 teaspoons of the mushroom mixture into the center of each wonton wrapper and bring each corner together to form a pyramid shape. Cover and set aside.
Place the stock, water, ginger, garlic, dried shiitake mushrooms, rice wine and sugar in a saucepan over high heat and bring to the boil. Reduce heat to low and cook for 15 minutes. Strain the broth and return to the saucepan. Increase the heat to medium, add the dumplings and fresh shiitake mushrooms and cook for 3-4 minutes or until wontons are transparent. Top with coriander and chili and serve with chili oil.
Notes
The original dumpling recipe called for galangal in place of the ginger, however I couldn't get hold of galangal. It also called for Chinese black vinegar in place of the rice wine vinegar I used. Dried shiitake mushrooms are available in the international food section of your supermarket otherwise try an Asian grocer.