Roast squash and sweet potato soup with buttermilk blue cheese sauce

Preparation time

less than 30 mins

Cooking time

30 mins to 1 hour

Serves

Dietary

Vegetarian

I have to have a regular supply of this squash and sweet potato soup at Christmas - it really is one of my freezer favourites.

By Nigella Lawson

From Nigella's Christmas Kitchen

Ingredients

1 onion, roughly chopped
1 butternut squash, unpeeled, halved, seeds scraped out, sliced into 2.5cm/1in x 2.5cm/1in cubes
500g/1lb 2oz sweet potatoes, unpeeled, cut into 2.5cm/1in thick rings
60ml/2fl oz olive oil
1 tsp ground cinnamon
½ tsp ground nutmeg
1.5 litres/2 pints 13fl oz vegetable stock
125ml/4oz marsala wine
salt and freshly ground black pepper

Preheat the oven to 200C/400F/Gas 6.
Place the onion, chopped butternut squash and sweet potato onto a baking sheet. Drizzle with oil and sprinkle with the cinnamon and nutmeg. Roast in the oven for 45 minutes to an hour, or until tender.
Allow the vegetables to cool slightly, then place half into a food processor and add 500ml/17fl oz of the vegetable stock. Blend to a purée and transfer to a large pan. Repeat with the remaining roasted vegetables and 500ml/17fl oz more of the stock - transfer the purée to the pan.
Add the remaining 500ml/17fl oz of vegetable stock to the food processor and stir to catch any remnants of the vegetable purée, then pour into the pan.
Add the marsala wine and season, to taste, with salt and freshly ground black pepper. Add a little more water if the soup is too thick for your liking.
For the buttermilk cheese sauce, place the blue cheese and buttermilk into a clean food processor and blend to a paste. Transfer the blue cheese sauce to a jug or bowl.
To serve, ladle the soup into bowls and drizzle some of the blue cheese into each bowl. Leave the sauce on the table for your guests to add more if they wish.