Chelow with Tahdig

Rinse basmati rice in several changes of cold water until it runs clear, then soak in fresh water with 1 tablespoon of salt for at least 1 hour (up to overnight).

Bring 3 litres of water to a rolling boil with the rest of the salt. Drain the rice, add it to the pot and boil, stirring gently once or twice, for 6 to 8 minutes until the grains are long and soft outside with a firm, white core. Drain and rinse briefly with lukewarm water.

Wipe the pot dry and heat 3 tablespoons of vegetable oil over medium heat in a nonstick pot. Mix 2 big spoons of the rice with plain yogurt and a third of saffron, and spread it in an even layer over the base.

Spoon the rest of par-boiled rice on top in a loose pyramid, poke 5 holes down to the base with a spoon handle and drizzle over the remaining oil. Cook uncovered on medium for 8 to 10 minutes until you hear a steady sizzle. Wrap the lid in a clean towel, cover tightly and steam on the lowest heat for 45 to 50 minutes.

Spoon a little rice into a bowl with the rest of the saffron and butter. Pile the white rice on a platter, scatter the saffron rice on top, then loosen and lift out the tahdig in one piece or in pieces and serve it alongside.