A story from Kashgar Old Town

Taken in Old Town in Kashgar, we stopped as I noticed fire reflecting off the panels in a dark alleyway and peered in. Looking up, he grinned and gestured for us to enter. At first glance we saw a young man cooking something over a fire. At second glance, we saw a pile of white goat skulls in one corner and a pile of charred goat skulls in another.

Goat Head Soup is sold throughout Xinjiang, but why char them over a fire first?