Chicken or duck stewed slowly in ground walnuts and pomegranate molasses until dark, thick and glossy — sweet and sour at once.
What makes it fesenjan
Walnuts ground fine and cooked slowly until their oil rises.
Pomegranate molasses for a deep sour-sweetness.
Poultry — chicken or duck — or sometimes small meatballs.
Where it comes from
It's often traced to Gilan, on the Caspian, where wild duck and walnuts were both at hand, and it's a dish for guests and celebrations. Cooked long and gently, the walnuts give up their oil and the sauce turns nearly black.
How sweet or sour it should be is the family argument: a little sugar in some kitchens, more pomegranate in others.