Favourite Spiced Parsnip Soup

This is our favourite parsnip soup, by Sarah Raven, and is just the best when we find ourselves snowed in here at Bethanie in the winter.

For 6:

30g butter
1 tbsp sunflower oil
1 onion, chopped
675g parsnips, chopped
1 tsp ground coriander seeds
1 tsp ground cumin seeds
1/2 tsp ground turmeric
1/4 tsp chilli powder
1.2 litres vegetable stock
salt and black pepper
A little milk (optional)
150ml single cream
yoghurt and chopped coriander to serve (optional)

Melt the butter with the oil in a large heavy-based pan and add the chopped onion and parsnips. Sweat them for 5 minutes, without allowing them to colour. Stir in the spices and cook gently for another 2 minutes.
Add the stock and bring to the boil. Reduce the heat, cover and simmer for about 30 minutes or until the parsnips are quite tender. Allow to cool slightly, season carefully and puree in a food processor.
Return the soup to a clean pan, adding a little milk if necessary, depending how thick you would like the soup.
Add the cream and warm through gently without allowing the soup to boil. Serve with a dollop of yoghurt and some chopped coriander.