To make the koftas, soak the bread in the milk for 2 minutes, then squeeze out the milk. Place the bread in a food processor, add the lamb, chilli, coriander, garam masala, garlic, ginger, mint, and salt to taste, then processs to a smooth mixture. Add the onions and pulse for 1 or 2 seconds, so they are mixed in but not puréed.
Transfer the mixture to a bowl, cover and chill for 30 minutes, or overnight in an airtight container.
Meanwhile, rinse the rice then place it in a bowl, cover with cold water and leave it to soak for 30 minutes.
Heat the grill to high, line the grill pan with foil and brush it with oil.
Divide the lamb kofta mixture into two portions. Lightly grease your palms and make 12 equal-sized balls out of each portion. Place them on the grill pan 1 cm (½ in) apart and grill for 5 minutes. Meanwhile, melt the butter.
Brush the koftas with half the butter and continue grilling for a further 2-3 minutes until they have browned.
Turn the koftas and brush with the remaining butter. Grill for 3-4 minutes until browned. Wrap them in a piece of foil and keep them warm.
Drain the rice and set it aside. Put a kettle on to boil.
Heat the oil in a large heavy saucepan or flameproof casserole over a medium heat. Sprinkle in the sugar and cook for 1-2 minutes until it has caramelised.
Add the cardamon, cinnamon and rice and fry them for 2-3 minutes, stirring continuously. Then pour in 475 ml of boiling water and add salt to taste.
As soon as the water returns to the boil, add the meatballs in a single layer, plus any cooking juices, then reduce the heat to very low. Cover the pan with a piece of foil and then the lid. Cook for 10 minutes without lifting the lid or the foil.
Take the pan off the heat and let it stand, undisturbed, for 10 minutes.
Transfer the rice and koftas to a serving dish and serve, garnished with cherry tomatoes and coriander.