Fesenjan

Fesenjan is chicken braised for two hours or more in a thick, dark sauce of finely ground walnuts and tart pomegranate molasses, reduced slowly until the walnut oil rises visibly to the surface and the sauce turns the deep brick-brown that marks it as done. It is one of Iran's khoresh — the slow-cooked sauces spooned over rice that form the backbone of home cooking — and the one most associated with the Caspian region of Gilan, where walnut trees and pomegranates both grow thick.

What it really is

Walnuts are ground fine, not to a paste, and simmered in broth for a long stretch until they release their oil and the mixture thickens on its own, no flour or cornstarch needed. Pomegranate molasses goes in for tartness, balanced against a little sugar — every batch of molasses differs in sourness, so a cook tastes and adjusts rather than following a fixed ratio. Chicken thighs, or traditionally duck, go in partway through and finish tender in the sauce rather than being seared first. Getting the balance wrong in either direction is the dish's most common failure: too much sugar and it tastes like dessert, too little and the walnuts turn bitter and sharp.

How it's served

• Ladled generously over plain or lightly saffroned steamed rice, sauce pooling into the grain
• At the center of the table for Yalda, the winter solstice gathering, when pomegranates are at their peak
• Rice plated separately so each guest controls how much sauce goes over it

How to write it on the menu

• Flag walnuts clearly — they are the base of the sauce, not a topping a guest can ask to skip
• Say chicken or duck plainly, since the dish reads differently depending on which
• Mention it is a slow-braised stew rather than a quick sauté, for guests choosing by how long a dish takes

The ingredients, allergens and dietary notes listed here describe a typical recipe. They are not a binding declaration for any particular restaurant: recipes, portion sizes and the products used can differ.