GET AHEAD You can make this on the day, if you prefer. Toast the coconut in a pan until lightly golden, tossing regularly, then remove. Put the rice into the same pan, cover with boiling kettle water and boil for 6 minutes, then cool quickly under cold running water and drain well. Tip into a bowl, squeeze over the lemon juice, add the toasted coconut and a big pinch of sea salt and black pepper and mix well, then cover and refrigerate overnight.
TO SERVE Gently heat the milk, adding the saffron to infuse. Rub the butter across the base of a cold 26cm non-stick frying pan, then sprinkle in the cardamom pods. Tip in the rice, then use your hands to shape into a dome. Use the handle of a wooden spoon to poke a few holes deep into the dome to help the rice steam and create vessels, so you can spoon in the warm saffron milk. Cover carefully with a scrunched-up sheet of damp greaseproof paper. Use tin foil to tightly seal the pan, then cook over a low heat for 20 minutes, or until the base is crispy and the rice is fluffy and hot through.