Aubergine Biryani

Ingredients

• 2 aubergines, cut into 3 cm chunks
• 2 onions, sliced
• 3 garlic cloves, finely chopped
• 25 g ginger, grated
• 300 g basmati rice
• 2 l water, for boiling the rice
• 2 tbsp vegetable oil
• 2 tbsp biryani masala
• 1 tsp ground turmeric
• 1 cinnamon stick
• 4 cardamom pods
• 400 g chopped tomatoes
• 500 ml vegetable stock
• 100 g full-fat Greek yoghurt
• 15 g coriander, chopped
• 15 g mint leaves, chopped
• 1 lemon, cut into wedges
• Fine salt

Method

1. Heat the oven to 220°C, 200°C fan. Toss the aubergine with 1 tablespoon of the oil, 1 tablespoon of the biryani masala, half the turmeric and a good pinch of salt. Spread it across a large tray with space between the pieces and roast for 25 to 30 minutes, turning once, until deep gold and completely tender. Crowded aubergine steams and stays spongy, so use two trays if needed.
2. Rinse the rice until the water runs nearly clear. Bring the 2 litres of water to a proper boil, salt it generously and add the rice. Cook for 6 to 7 minutes, until the grains are flexible but still firm in the centre, then drain very well.
3. Heat the remaining oil in a wide, lidded casserole over a medium heat. Add the onions and cook for 10 to 12 minutes, stirring regularly, until deeply golden. Lift out one-third and keep it for the top; that crisp onion is the finish, not decoration.
4. Add the garlic, ginger, cinnamon, cardamom, remaining biryani masala and turmeric. Fry for 1 minute, until fragrant, then add the tomatoes and stock. Simmer briskly for 8 minutes, until thick enough that a spoon leaves a trail across the pan.
5. Fold in the roasted aubergine and cook for another 3 minutes. Pull the pan off the heat before stirring in the yoghurt and half the coriander and mint. Boiling yoghurt makes it split, so let the residual heat do the work. Taste and add salt if needed.
6. Spread the drained rice evenly over the aubergine mixture without stirring the layers together. Cover tightly, set over the lowest heat and steam for 12 minutes. Turn off the heat and leave it covered for another 10 minutes; lifting the lid early throws away the steam that finishes the rice.
7. Loosen the rice from the edges with a fork and gently lift some of the aubergine through, keeping streaks rather than making one uniform mixture. Scatter over the reserved onions and remaining herbs, and serve with lemon wedges for squeezing.