Fesenjan

Step 1: Toast 9 oz walnut halves in a dry frying pan over a medium-low heat for 5–6 minutes, shaking the pan, until they smell nutty and have a few golden patches. Let them cool, then grind in a food processor to a fine, damp crumb, like wet sand.

Step 2: Heat 2 tbsp vegetable oil in a heavy pot over a medium heat and fry 1 onion for 8 minutes until soft and pale gold. Stir in ½ tsp ground turmeric for 30 seconds.

Step 3: Add the ground walnuts and stir for 2 minutes, then pour in 3 ¼ cups water and bring to a gentle simmer. Cover with the lid slightly open and cook over a low heat for 45 minutes, stirring every 10 minutes and scraping the bottom, so it doesn't catch.

Step 4: Stir in ½ cup pomegranate molasses, ½ tsp ground cinnamon and 1 tsp salt. Keep simmering gently for another 15 minutes. The sauce should darken and small pools of walnut oil should appear on top. Taste: if it is very sour, add 1 tbsp sugar a teaspoon at a time; it should be tangy with a soft sweetness behind it.

Step 5: Meanwhile season 1 ¾ lb boneless, skinless chicken thighs with ½ tsp black pepper. Keep raw chicken on its own board and wash the knife and your hands afterwards. Nestle the pieces into the sauce, cover and simmer over a low heat for 35–40 minutes, stirring now and then, until very tender.

Step 6: Check the thickest piece: it must reach 165°F (165 °F) inside, or show no pink and run clear juices when cut. A common mistake is serving it too soon, when the sauce is still beige and thin; it should be dark brown and thick enough to coat a spoon. If it is too thick, loosen with a splash of hot water.

Step 7: Rest off the heat for 5 minutes, then serve over 4 portions cooked saffron rice (chelow), scattered with 3 tbsp pomegranate seeds. Fesenjan tastes even better the next day; cool, cover and refrigerate within 2 hours and reheat until piping hot all through.