Thai Coconut Curry with kaffir lime leaves and butternut squash

large butternut squash (1kg or 2lbs approx)

water

kaffir lime leaves

cardamom pods

heaped teaspoon grated ginger

large garlic cloves

celtic sea salt

heaped teaspoons ground coriander

turmeric powder

black pepper

passata (called sieved tomatoes in the US)

cooked chickpeas

creamed coconut (see notes)

spinach ( a large handful)

Small handful of fresh basil leaves