Bulbous, knobbly celeriac is an under-used vegetable, I find. Perhaps it is because it is probably one of the least attractive! Brown, rough and coarse-looking – don’t judge it by its looks! Its homely appearance hides a beautiful personality. Celeriac is widely used in Europe as a side veg, in soups, salads and stews. Its delicate celery taste is wonderful.
This soup is inspired by the recipe of one of my favourite chefs, Jamie Oliver. As I made his recipe, I made the adjustments as follows. His use of truffle oil, in my opinion, elevates the soup from “delicious” to “OMG spectacular” 🙂 you could, however, omit it and still have a lovely end product.
A note about truffle oil…consider it like perfume. A hint is lovely, but a lot is “too much”. Be mindful that different makes of truffle oil vary widely with regards to intensity and flavour. So, if you decide to use it, add it one tablespoon at a time as its flavour can very easily overwhelm the other flavours in the soup. For this quantity, I used about 3 tablespoons of good-quality white truffle oil.
1 onion, chopped coarsely
1 clove of garlic, chopped coarsely
500g/1 lb. celeriac (one average sized root), peeled and coarsely chopped
500g/ 1 lb. potatoes, peeled and coarsely chopped
2 tbsp. butter
2 tbsp. olive oil
2 tsp. dried thyme
1.5 litres vegetable stock (can use chicken stock), divided
1 cup heavy cream
salt and pepper to taste
3-4 tablespoons truffle oil, or to taste
chopped parsley to garnish
Heat olive oil and butter in soup pot and gently saute onion and garlic until transparent and soft, but not brown. Add celeriac, potato, thyme and one litre of the stock. Bring to boil, lower heat and cook gently for 35-40 minutes or until celeriac and potatoes are soft. Add the cream, and bring back to boil for a minute.
Remove from heat and puree with an immersion blender until completely smooth. Once vegetables are pureed, you might find the soup is a bit thick. If this is the case, thin it with a bit of the remaining stock, a little at a time, until you reach the consistency you like. Season to taste with salt and plenty of freshly ground pepper.
If you are using the truffle oil, add it now, a tablespoonful at a time. Stir each spoonful in well – it will “sit” on the top at first. Taste after each addition to make sure the truffle taste is there but STOP when you are happy with it. More is not necessarily better in this case.
Serve sprinkled with the chopped parsley as a garnish.