Tahchin Sabzi (Saffron Rice Cake with Spinach)

Dissolve the saffron threads in 2 tablespoons of hot water.

Peel and slice the onion.

Rinse the rice under cold water until it runs clear.

Wash and roughly chop the spinach.

Heat a little of the melted butter in a large saucepan, add the sliced onion and ground turmeric and cook until softened, about 5 minutes.

Add the spinach to the pan and cook, stirring, until wilted and any liquid has evaporated, about 6 minutes.

Bring a large saucepan of salted water to the boil, add the rice and cook for 6 minutes until just parboiled, then drain.

In a mixing bowl, whisk together the yoghurt, eggs, half the dissolved saffron water and the remaining salt, then stir in the parboiled rice to coat evenly.

Grease a loaf tin generously with a little of the remaining melted butter, then press half the rice mixture into the base.

Scatter the wilted spinach evenly over the rice layer, then top with the remaining rice mixture, pressing down firmly.

Drizzle over the remaining saffron water, cover the tin tightly and cook over low heat on the stovetop until the base is deep golden and crisp, about 45 minutes.

Rinse the dried barberries in a fine-mesh sieve.

Warm the last of the butter in a small saucepan, add the barberries and toss for 2 minutes until glossy.

Run a knife around the edge of the tin, invert the tahchin onto a board, scatter with the glossy barberries and slice to serve.