Tongabezi Chicken Curry

Ingredients

• sweet potatoes
  2 unit
• butternut squash
  1 unit
• chicken joints

  halved
  4 large
• salt
  1 unit
• freshly ground black pepper
  1 unit
• vegetable oil
  1 unit
• onions

  finely chopped
  2 unit
• tomatoes

  skinned, seeded and diced
  2 unit
• garlic cloves

  finely chopped
  2 unit
• (½ oz) fresh root ginger

  finely chopped
  15 g
• cardamom seeds
  6 unit
• heaped teaspoon curry powder
  1 unit
• (¾ pint) chicken stock
  450 ml
• sticks lemon grass

  bruised
  2 unit
• red chilies

  finely chopped
  2 small
• (½ pint) yogurt
  300 ml
• finely chopped fresh coriander
  1 tablespoon