Zuo Rensi, another great-great-great grandson, opens the decaying gate of his ancestor's courtyard home and leads visitors quietly into what was once the kitchen. He speaks quietly of the dish known here as "Zuo gongji" or "Zuo's rooster."
"I don't know if he created the dish or it was made for him," Zuo says. "But we all know about it. No one knows how to make it anymore though."
Aside from his formidable military career -- including campaigns to crush the Taiping Rebellion and an uprising in the predominantly Muslim western region of Xinjiang -- Zuo was known for his belief that China needed to modernize to survive. His method: using tried-and-true Western innovations to improve upon Chinese traditions.
This is instructive when considering the global journey of General Tso's chicken. In a recent random sampling of more than a dozen restaurants in Hunan province, only one -- near Changsha's main train station -- offered Zuo's rooster on the menu.
What arrived was a melancholy mix of vegetables, shallots and greasy, scrawny pieces of chicken studded with perilous slivers of bone -- a far cry from the juicy, boneless poultry chunks familiar to Americans.
"Chinese are going all over the world, and they're taking their recipes with them. It can only get better and more professional," says Chen, the cooking-school instructor.
Usually, though, the Chinese version of Chinese food is far tastier than its American imitation. Not this time. And there's not a Zuo in town who can explain why.
"All the Zuos who could leave here left. Maybe they took it with them," says Zuo Jingyou, who doubts that he will ever make it to the United States to sample the descendant of his ancestor's eponymous meal. "I don't know the story of the dish. I really wish I did."