Sweet potato & chestnut soup with blue cheese toasts

Method

1. Peel the sweet potatoes and cut into roughly 3cm chunks. Heat the oil with the butter in a large saucepan. Add the sweet potato and onions and cook over a gentle heat for about 10 minutes until the onions begin to soften but not colour. Add the cumin seeds and paprika. Season with salt and pepper. Cook for a further two minutes.
2. Add the chestnuts and stock. Bring to the boil then lower the heat and cook partially covered with a lid for 15 minutes. Remove the lid and grate in some fresh nutmeg. Cook for five minutes before blitzing with a hand blender until smooth. 
3. Meanwhile, preheat your grill to hot. Toast the bread slices under the hot grill until lightly golden on both sides. Turn off the grill, crumble over the blue cheese and return to the grill to melt slightly.
4. Serve the blue cheese toasts with a dollop of crème fraîche.