Carrot and Celeriac Soup

1 celeriac (cut all the hard outer skin off with a knife and cut into cubes)
4 - 6 carrots (peeled and cubed)
1 onion (chopped)
1 leek (white only - chopped)
2 - 3 sticks of celery (chopped)
Vegetable stock
Salt and pepper
1/4 tsp Nutmeg
1 tbsp of vegetable oil

Cook the onions on a medium heat in a large pan for around 5 minutes until they are clear. Add the celeriac, carrot, leek and celery and cook for another 5 minutes. Cover all the vegetable with stock. Put the heat on full until the vegetables are boiling and then reduce to a simmer and fit a lid. Leave to cook for half an hour or until the carrots are soft. Puree the soup in a blender and add 1⁄4 tsp nutmeg, salt and pepper to taste.