THE Yellow River carves its way out of the Helan Mountains,giving birth to the alluvial Ningxia Plain,a typical oasis in the Gobi Desert.For thousands of years,this amazing place has been reputed as a fertilized region on the remote border.Nearly all Chinese gourmands believe that the Ningxia Plain produces the best mutton.It is said that stewing the mutton without flovouring is the best way to cook it.