Leek, chickpea & sweet potato soup with harissa

1. Heat the olive oil in a large saucepan and add the leeks and garlic. Cover and cook gently together for about 10 minutes until soft but not browned, stirring occasionally. Add the sweet potato and cook for a further 5 minutes.

2. Add the can of chickpeas with their juices (reserving some whole chickpeas to garnish the soup), the sage, stock, seasoning and about 100ml cold water. Bring to the boil and simmer together for 10-12 minutes until the potato is tender.

3. Purée the soup in the pan with a stick blender or whizz in a food processor, but don’t make it completely smooth – it’s nice to have a bit of texture. Reheat, check the seasoning and add a splash more boiling water to loosen if needed, then spoon into warm bowls.

4. Combine the harissa with the mixed seeds and reserved whole chickpeas, and scatter over the soup. Serve with your favourite extra virgin olive oil to drizzle over, along with grated Parmigiano Reggiano.