Tahdig
Tahdig is the crispy layer of rice from the bottom of the rice cooking pot – for many people it’s their favourite part of a dish of Persian rice.
Method
Put the rice in a bowl and cover with cold water; swirl round until the water is cloudy, then strain off. Repeat several times until the water is virtually clear. Cover the rice with fresh water and leave to stand for 30 minutes.
Pour a couple of kettles of freshly boiled water into a large saucepan. Add 1 heaped teaspoon of salt and bring back to the boil. Add the drained rice and boil for 5 minutes. Drain the rice and rinse under cold water.
Meanwhile, crush the saffron with a generous pinch of sea salt using a pestle and mortar. Add 2 tablespoons of freshly boiled water and leave to steep for 10 minutes.
Put the yoghurt in a bowl and drizzle over 1 tablespoon of the saffron water. Add 300g/10½oz of the parboiled rice and mix thoroughly. Stir in a couple of tablespoons of the melted butter.
Heat the olive oil in a large lidded frying pan or shallow casserole – ideally 25–28cm/10–11in diameter. Spread the saffron rice evenly over the bottom of the pan, pressing it down lightly. Mix 1 teaspoon of salt with the remaining rice and sprinkle this over. Using the handle of a wooden spoon, poke holes into the rice – this will allow steam to escape from the bottom of the pan and help the bottom layer to crisp up.
Mix the remaining saffron water with the remaining melted butter. Pour this over the rice, allowing some of it to drip into the holes.
Wrap the lid in a tea towel and place on top of the pan. Cook over a medium heat for about 10 minutes, then turn the heat to very low and leave to cook to allow the crust to form. If cooking on gas, move the pan around every few minutes to make sure it cooks evenly (and doesn’t burn in the middle).
After about 25 minutes, start checking the crust. Carefully lift an edge of the rice with a palette knife – if it is starting to look crisp and brown around the edges, it should be done. This may take up to 40 minutes.
Remove from the heat and leave to stand, keeping the tea towel and lid in place, for 5 minutes.
To turn out, carefully go round the edges with your palette knife, checking to see if the crust comes away cleanly. When you are sure you have a reasonable chance of it turning out intact, upturn the pan onto a large serving plate. If it doesn’t come away cleanly, pull the crust off and arrange it over the rice – this is a perfectly acceptable way to serve it!