Nigella lawson's pumpkin and chickpeas soup

Ingredients

• 500 g Japanese Pumpkin
• 200 g boiled / canned chickpeas
• 200 ml coconut milk
• 2 tbsp curry powder
• 1 tbsp sugar
• 1 tsp turmeric powder
• 1 lime leaf, torn / grated lemon rind
• 1 lemon grass crushed
• 1 onion chopped
• 1 tbsp minced garlic and ginger
• 1 vegetable soup cube
• 2 tbsp vegetable oil
• Salt and pepper to taste
• Spring onion chopped
• Coriander leaves for garnishing