Chicken with spinach

Name: Chicken with spinach
Ingredients: 500g/1lb 2oz spinach leaves, washed; 4 tbsp vegetable oil; 3 cardamom pods; 2 bay leaves; 5cm/2in piece cinnamon stick; 3-4 green chillies, pricked with a knife; 1 large onion, chopped; 2cm/¾in piece ginger, peeled and chopped; 1 head garlic, peeled, cloves left whole; 3 large tomatoes, cut into quarters; 800g/1lb 12oz chicken pieces, skin removed; 2 tsp ground coriander; 1½ tsp garam masala; salt and freshly ground black pepper; 4 tbsp plain yoghurt, stirred; basmati rice, cooked according to packet instructions, to serve