This dish originates from Qin town in the Shanxi province of China. The recipe takes a little time to make, but the results are really worth it.
Soybean sprouts can be purchased in Chinese/Oriental speciality shops. If unavailable, use beansprouts instead.
Oh wow. I remember many years ago, cookery school experiments where we had to make balls of dough, knead them and rinse in water until we were left just with balls of gluten. Just to show the difference between hard and soft flours. Thanks for reminding me :D - 27 Feb 2016