This is probably one of my favorite dishes in Chinese cuisine. My mom used to make this for us once every few weeks when I was growing up in Hong Kong but with different crabs (since there were thousands of different varieties of crab). We only had Dungeness crab in Canada and the U.S.
Along with two simple and quintessential Chinese ingredients, ginger and scallions, and rice wine, brown sugar plus soy sauces, you can have this often very expensive dish in the comfort of your own home.
Personal tidbit: save the sauce to dress noodles for lunch the next day. Delicious.