Moroccan spiced pie

INGREDIENTS

• 2 tsp each coriander and cumin seeds
• 1 tsp paprika , plus extra for dusting
• ½ tsp ground cinnamon
• 150ml/¼ pint olive oil
• 900g squash , peeled and cut into small chunks (about 2cm)
• 12 shallots , quartered
• 4cm/1½ in piece root ginger , finely chopped
• 140g whole blanched almonds
• 140g shelled pistachios
• 75g pack dried cranberries
• 6 tbsp clear honey
• 225g pack fresh spinach
• 400g can chickpeas , drained and rinsed
• 2 garlic cloves
• 1 tsp ground cumin
• 3 tbsp lemon juice
• 4 tbsp chopped fresh coriander
• 100g butter
• 8 large sheets of filo pastry
• lemon wedges to serve
• 200g carton Greek yogurt
• 6 tbsp milk
• 3 large sprigs mint , leaves chopped
• 2-3 tbsp harissa paste