Veggie meatball biryani

Name: Veggie meatball biryani
Ingredients: 4 tbsp whole milk; small pinch of saffron; 120g/4½oz thick, plain natural yoghurt; 2 tsp finely chopped ginger; 2 tsp finely chopped garlic; 2 tsp ground coriander; 1 tsp ground cumin; 1 tsp chilli powder; 1/2 tsp ground turmeric; 350g/12oz long-grain basmati rice, rinsed well and soaked in cold water for 2 hours; 1 dried Indian bay leaf; 4 green cardamom pods, slightly cracked with a pestle or bottom of a cup; 5cm/2in cinnamon stick; 3 cloves; 100ml/3½fl oz melted ghee or neutral oil; 2 large brown onions, finely sliced; 300g/10½oz frozen veggie meatballs; 120ml/4fl oz hot kettle water; 1 tbsp mint leaves, roughly chopped; 2 tbsp coriander leaves, roughly chopped; 2 tsp salt; 3 tbsp pomegranate seeds, to garnish