Tachin (Persian Saffron Rice Cake)

Tachin is the showstopper of Persian rice cookery — a saffron-yellow rice cake baked in a tin until the bottom forms a deep, golden, audibly crisp crust called tahdig. Par-boil basmati rice, then fold most of it into a custard of egg yolks, thick yogurt, saffron-infused water and butter. Press half this mix into a buttered tin, layer in cooked filling (chicken, lamb, or barberries), top with the remaining rice, and bake covered then uncovered until the bottom is set and golden. Inverting it onto a plate without breaking the crust takes nerve. Eat the same day; reheating destroys the texture.